The S-Works M5 Hardtail was created as my backup bike for light trails/ commuting. The idea was to build a decent handling bike which was relatively lightweight while remaining fairly durable. The evolution of the M5 hardtail from my backup bike to a solid alternative to my Epic is reflected in the early build of the bike - initially it was equipt with XT transmission, Mavic Crossride (2006) wheelset and whatever spare parts I had lying around. This changed when the decision to employ it as a capable light XC/ race-ready rig was made.The S-Works M5 HT also served as my "testbed" for the 07 XTR groupset - the current build includes a full 97-Series groupset - including the wheelset. Thus far, the 97 series XTR componentry has proven itself to be a vast improvement over the previous generation and stands as a serious competitor to the present incarnation of SRAM X.O. While shifting may not be as crisp or positive as X.O, it's not far behind and makes up for this by being somewhat smoother. The mechanical feedback from the transmission is a fair bit lighter than X.O, but this will certainly delight those who feel that the X.O is too jarring - indeed, I feel that present XTR does a great job of balancing smoothness with positive feedback. The biggest improvement in the transmission has probably been the shifting - particularly in the Dual-Control department. Shifting with the previous generation of Shimano XTR Dual-Control levers was a somewhat labourous and uncertain affair - you had to activate the up/down shift waaay in advance because only when the lever was released after being depressed did the shifters finally start to engage. The fit and feel of the new Dual-Control levers is also very well thought out - they are far more ergonomic than the previous ones (their positioning and construction is first class throughout.Braking with the XTRs is first class - they may lack the brute stopping power of some other brakes in the class, but they make up for it with a very smooth and controlled feel - the sound and feel of the pads upon contact with the rotors is a smooth and reassuring one and brake stutter is almost non existent. The alloy levers move in a very smooth and controlled manner and feel extremely well made. However, one noticable problem is that with the stock cables applied, the brakes do lack that bit of positivity and the maximum extent of the lever pull is hard to determine - probably because of the excessive flex in the stock cables - a quick trip to get Goodridge cables and fittings fixed the problem and the brakes now combine that excellent modulation with enhanced smoothness and positivity. Stopping power with 160mm rotors front and rear is awesome and the rider never really gets the feeling that the bike is running away from you because the brakes work magnificently.The present generation XTR hubs (an experience granted courtesy of the XTR wheelset) are also quite a revelation. Engagement is far more positive than previous XTR and the smoothness of the hub when rolling is evident to the user not only in the feel but the almost soothing and soft buzz of the freehub. The new scandium rims seat tires very securely and are not only light but fairly durable to boot - their toughness and ease of cleaing being enhanced by the application of a quality anodized finish. The wheels are hardly the lightest in the market - but weight has indeed been saved when it matters most - away from the hubs. In additon to the rims, lightweight doublebutted spokes are employed in the construction of the wheels - this is perhaps where the wheelset's greatest weakness lies - the double butted spokes are tangibly flexier than many other offerings on the market - if one had to compare the two wheelsets I use most (the Crossmax SLR and the XTRs), I'd have to say that the Crossmaxes make up for their somewhat heavier weight by offering a much stiffer and sturdier feeling build, but are trumped by the XTRs in terms of hub build quality and engagement. Overall, the XTR wheelset feels FAST but requires a bit more confidence as the flex is particularly evident on fast and hard corners and over the rockies.   The contact points of the M5 hardtail took a while to solve. Early builds included Specialized BG Comfort grips, BG Rival SL saddle and Crank Brothers Candy Ti pedals. Gradually, the selection of parts changed to include those that I found worked best during my experiments on my other bike. As a result - much of the cockpit componentry is identical for both bikes.In the interest of mating comfort with low weight, the Specialized Toupe Team saddle I favor was mounted on an Easton EC90 seatpost - the flex of the Saddle working in tandem with the flex and vibration damping qualities of the seatpost - the result is a suprisingly comfortable hardtail - a fairly drastic change from the previous setup. The lower weight also means that the bike is more managable as the decresed mass at the saddle and post requires less effort by the rider to counter.Minor additions to the build include the addition of a Salsa seat collar - both for looks as well as the perceptibly more secure clamping over the stock specialized one and the fitting of Ti and Alu bolts where possible. These changes served to drop a fair bit of weight as well.One small expriment served to shave a few grams and add a bit of colour to the bike as well - Tiso lockrings were swapped in for the stock Shimano lockrings as used to secure the rotors - 2g off each wheel and a bit of bling to go with it. Alu presta valve caps - in the same shade as the nipples on the wheelset served to add another tiny touch to the bike.Most recently, in an effort to get the bike to fit more comfortably, the OS115 stem was replaced with a slightly longer and lighter OS99 stem. Having used the Syntace F99 stem, I can honestly say that the OS99 is very much stiffer than equivalent Syntace offerings and has the advantage of accomodating oversize bars, and coming stock with Ti bolting at stock where the Syntace did not; the result? A lightweight (99g~) stem at a decent price - one that undercuts the  stock Syntace slightly.To complement the low slung feel of the M5 - a feel that it shares with the Epic, many changes were made, particularly to tire selection in an effort to find the right tire - tire height plays a significant part in influencing the height of the BB and thus the CG of the bike. Thus far, the Specialized S-Works Roll X tire has performed admirably, the decent high keeping the BB at a decent height (not too low, not too high) while providing solid grip, fairly smooth rolling tire and relatively low weight.Swapped out the stock Steel caliper bolts for Ti ones - saved about 3.5g per bolt for a total of 14g down. Simply and affordable weight saving from a relatively minor part.As I've had tremendous satisfaction using the KMC X9-SL chain on my Epic, I decided to apply one to the M5 as well - it's easily the best chain I've ever used. Shifting is smooth, chainslap is much reduced and the transmission seems to have a smoother "flow" to it. On top of that - these chains seem to last forever and shave weight in the process. I highly recommend them. As mentioned elsewhere, the only issue one might have with the X9-SL is with the drivetrain picking up more sand than usual compared to solid plate chains - not that much of an issue if you know how to clear the chain on the go.I was interested in trying out the new Shadow Derailleur and managed to get one via Hup Leong. Thanks to "The Rabbit", the setup is now up and running. Performance so far has been impressive - the derailleur action is a bit more postive than the "conventional" XTR dereailleur. The cage tension also seems to be a little better and chain slap seems much reduced, although, this might also have something to do with the KMC X-9SL chain applied to the bike. Workmanship is not bad, but I have to admit that while the carbon looks nice, there is a distinct sense that the industrial look of the aggresively machined alloy cage and the finishing on the parallelogram  of the standard derailleur seem to be a little better. One other issue is that the cables have to be cut fairly precisely as the angle they exit the derailleur goes directly to the spokes, so some care must be exercised there. Will report back on performance once more miles are logged in. - UPDATE: The XTR Shadow Rear  Derailleur has performed exceptionally over the past few months - though use has been limited to gentler trails and road riding. Shifts are crisp and responsive and the transmission definitely feels more "taut" than with the conventional XTR rear D. The great advantage of the XTR shadow rear D, in my humble opinion, is that the lack of the secondary spring in the mechanism really does eliminate a great deal of the transmission clanking as a result of the unit striking the chainstay. This is just as well given that the cage of the unit is quite fragile - as some riders have already found out. Additionally, while I have gotten used to the combination of this derailleur and the Dual-control shifting interface, I have to admit that it it not necessarily ideal, especially given situations where the incline works with gravity to make shifting particularly difficult - e.g. going downslope where your intention is to up-gear - I therefore agree with the sentiment that DC works best with Low-Normal designs. However, as with most things, it is a matter of getting used to and if the rider's personal preference is to have the shadow paired with the DC shifters, that's perfectly fine - I have thusfar adapted to its limitations. In conclusion, I must say that the Shadow rear D isn't really something that everyone is going to like, particularly those who intend to ride hard. In spite of it's design, it's not immune to damage on the trail and the carbon cage is particularly delicate - hard riders who are pro-shimano would therefore be better served by the standard XTR rear D with it's more durable cage and forgiving nature. However, for those who are simply looking for light - this is certainly the lightest stock offering for the mass market and worth a consideration.Added red crank protectors and red alloy rotors to the setup. The former adds a little of protection to cranks while the latter sheds a bit of weight off the standard XTR rotors - both add a splash of colour.The M5 is currently being used as my testbed for the 32mm SID. So far, it's quite promising and the feel of the new fork is pretty awesome. I'm currently running it as an 80mm travel unit and from the start, the fork's characteristics have been quite obvious. It's firm and "racey" feeling, but also relatively controlled. Initial stroke is decently plush and smooth, but it firms up pretty quickly meaning that out of saddle climbs and sprints are not a problem at all. The travel on this unit feels a more progressive than on the previous SID, and indeed the Reba as well - something that will be a bit of a hit or miss depending on the crowd you ask. Also, compared to the carbon crown and steerer World Cup forks, the alu one feels a little harsher (on par with most other alloy crown and steerer forks on extended gravel and road sections), but the tradeoff is that you feel more "direct" and in touch with the ground. The settings on the new fork are quite comprehensive and I'm still having a great time experimenting with the settings. On durability, no comments so far, but apart from the fact that white forks get dirty in a very obvious way (meaning a lot of cleaning), I haven't seen any real causes for concern from the elements that really matter (e.g. seals).Spec List:Specialized S-Works 06' M5 HT FrameRockShox SID World Cup (Black/Red)RockShox SID Team (White/Red) - (test fork)+ Chris King Red Anodized Stem Cap and Ti bolt.Shimano XTR FC-M970 CranksetShimano XTR BB with Enduro Ceramic Hybrid Bearing upgradeShimano XTR FD-M970 Top Swing Front Derailleur with alu bolt (Red)Shimano XTR CS-M970 11-34T CassetteShimano XTR RD-M972 Shadow Long Cage DerailleurShimano XTR ST-M975 Dual Control Levers with Goodridge brakeline upgradeShimano XTR BR-M975 Calipers - Secured with Ti boltsShimano XTR SM-RTB97 160mm Rotors - Secured with (Red) Tiso Lock Rings/ Red Alloy 160mm Rotors secured using DT Swiss 6-bolt AdaptorsKMC X9-SL Silver Chain FSA OS99 StemRace Face NEXT SL Flat BarSpecialized Mountain BG GripsSpecialized BG Toupe Team SaddleEaston EC90 Seatpost 30.9Token SeatclampCrank Brothers Acid 2 Pedals (Black)Primary Wheelset:Shimano XTR WH-M975Alternative wheelsets and tires as per the Epic