i really can't decide which bike to get! i really want a 4 stroke and like the fact that i can get a used 2001 yz426 for $4000, but i don't want the yz450 to immediately outdate it. i don't know though, i am only 125 lbs. so i think the 426 could make me fly. how are these things for trail riding? how are they for jumping, and i know it is heavy but could you do a little freestyle on one?