Got a one year old model and i'm glad i spent that bit extra on it.
The 8000, is aimed at your cross country racer. Whilst is decends pretty good (tracks well, forks work right up to their limits) it aint no downhiller heavy weight thing. This will climb back up to the top with less effort than a 2 man chair lift.
The traction is there right where you need it, under your back side. The tyres they come with however, are designed for the moab desert, so thats your first upgrade (Velociraptors are my choice). The 27 speed XT/LX kit is good, if not a little temperamental. The narrow chain does not like to go out of shape or you'll end up spontaneously changing gear. Likewise, the narrow chain puts more pressure on your rings causing them to wear quicker. Make sure you change your chain at least every 6 months to reduce the amount of kit you'll get though (chainrings, cassette). A good sedis is quite adequate.
The contact points are well catered for (grips, saddle and SPD peddals) and the seat post, handle bars and stem are all decent light weight stuff. If you like a simple, no nonsense lightweight MTB that will last you a hell of a long time then look no further. Have fun.
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