Hardtail or Full Suspension? Most likely this is based either on preference or on local trails you plan to race/ride. Most of the MTB world has moved to full suspension, but a lot of times it will be overkill.
Start by trying some out. Check out your local shops and see what all the other fast guys are riding and which shops are active in your local MTB scene.
Kona Hei Kei Supreme
Fisher HiFi Plus 29
Jamis Dakar XCR Expert
They all go really fast, all will surely feel different given all the different suspension setups and components. Find something you feel comfortable on and check out any demos in your area.
Last edited by mrchristian; 06-02-08 at 07:17 PM.