A $4,000 budget gives you lots of options so you should have plenty from which to choose. Just went through the process myself, albeit on a more modest budget. I'm 6' tall and about 225 lbs so was looking for a solid bike (6+6 or 7+7) to do mostly aggressive trail riding but also some downhilling and freeriding. Looked seriously at the Banshee Chaparral, Devinci 8-Flat-8, Cannondale Gemini 2000, Norco Six, Santa Cruz Bullit, and Yeti ASX. The Norco Six is almost impossible to get and the 8-Flat-8 was nice but pretty heavy and seemed geared more much toward downhill. The rest are similar and are all very competent bikes. In the end, I simply couldn't justify spending $750 to $1,500 more for a Chap, Bullit, or ASX so bought the Gemini and am very satisfied so far. The only thing I've done is put some bigger tires on it (2.5 Kenda Nevegal on front and 2.35 on rear). The 2.35 High Rollers that come stock are nice for trail riding but measure much narrower than their size suggests and the low profile knobs don't provide enough traction for my riding. The Nevs measure true to size and with them and the stock suspension (tuned correctly), the Gemini is pretty much "point and shoot". Simply runs over anything in its path yet allows me to stay in control. Has definitely improved my riding. Everyone who rides it is suprised at how light it is and how easily it pedals. Hope this helps . . . good luck with your decision.
