IMO i hate the smith machine... its good for a few advanced variations of the squat, but for regular back squats its just too hard on the body because your body doesnt go exactly straight up and down...

__________________
age-20
6'0" 190lbs
bench press-245x2
a2g squats-455x1-9/7/06
deadlift-475x1-9/5/06

"An ounce of prevention beats a pound of cure."