Go cannondale jeckyll (at least jeckyll 800)
Its the best all mountain bike on the market in my opinion. I have the 800. The lefty fork alone makes it the best XM bike out there. But it's got plenty more to rave about. The spec. fsr is a great bike, but the only thing i think it has over the jeckyll is maybe 1-2 lbs., and maybe a slightly better pedal platform (little bob) with its four bar linkage suspension. That being said, the jeckyll has a fox pro pedal shock w/ lockout, so it also has very little bob. You would only notice the difference in bob if you tried really hard, or race expert class xc. The weight difference is nominal, but if you are a weight weenie, then I'll say this - you won't notice the weight difference in climbing as much as you notice the plush, stable ride decending on the jeckyll. The single pivot design is also more plush, and progressive IMO. More importantly, it needs less matainence because it has less pivots, and isn't as complicated. Four bar linkage fsr's also widen the wheelbase more than single pivot designs when the suspension compresses, so they don't coner as well. The jekyll corners like it was on rails (after you replace the crappy stock tires). It tracks sooo nice! I also have an Intesne M1 for downhilling, which shares the same rear linkage system as the Spec. FSR. So I experience the differences first hand very often.
Now, back to the Lefty fork. IMO, it's the best 4-5" travel fork on the market. It's unrivalled in stiffness (on one leg means NO FLEX), it's sooo progressive (air assist), weighs less than any fork in it's class, great rebound adjustment, and it the coolest looking thing I've seen on a mountain bike (don't get it if you don't like people oogling over you bike). Certain Lefty's have lockout too, which is awesome on fireroad climbs. When I lockout bout suspensions, the jeckyll feels like a road bike.
Lastly, aesthetics. If you care about looks, this is one of the sickest looking bikes out there! But don't take my word for it, go test ride every bike you can! Then buy the Jekyll
Check out the reviews too, most Jekyll owners will say the same thing. If anyone from C-Dale reads this, send me some free stuff!! 

Its the best all mountain bike on the market in my opinion. I have the 800. The lefty fork alone makes it the best XM bike out there. But it's got plenty more to rave about. The spec. fsr is a great bike, but the only thing i think it has over the jeckyll is maybe 1-2 lbs., and maybe a slightly better pedal platform (little bob) with its four bar linkage suspension. That being said, the jeckyll has a fox pro pedal shock w/ lockout, so it also has very little bob. You would only notice the difference in bob if you tried really hard, or race expert class xc. The weight difference is nominal, but if you are a weight weenie, then I'll say this - you won't notice the weight difference in climbing as much as you notice the plush, stable ride decending on the jeckyll. The single pivot design is also more plush, and progressive IMO. More importantly, it needs less matainence because it has less pivots, and isn't as complicated. Four bar linkage fsr's also widen the wheelbase more than single pivot designs when the suspension compresses, so they don't coner as well. The jekyll corners like it was on rails (after you replace the crappy stock tires). It tracks sooo nice! I also have an Intesne M1 for downhilling, which shares the same rear linkage system as the Spec. FSR. So I experience the differences first hand very often.
Now, back to the Lefty fork. IMO, it's the best 4-5" travel fork on the market. It's unrivalled in stiffness (on one leg means NO FLEX), it's sooo progressive (air assist), weighs less than any fork in it's class, great rebound adjustment, and it the coolest looking thing I've seen on a mountain bike (don't get it if you don't like people oogling over you bike). Certain Lefty's have lockout too, which is awesome on fireroad climbs. When I lockout bout suspensions, the jeckyll feels like a road bike.
Lastly, aesthetics. If you care about looks, this is one of the sickest looking bikes out there! But don't take my word for it, go test ride every bike you can! Then buy the Jekyll

