Hi

I am buying my first mountain bike and need some advice on what to buy. I checked out a bunch of bike shops and found 3 bikes that I think are fairly comparable and all have disk brakes, but differ in price...any advice on which I should go with and why???
1. Giant Yukon for $423
2. Trek 4300 fir $387
3. Raleigh 05 M59 DX

Any advice would be really helpful!!!
Thanks!!