Spent a good deal of time riding both bikes this last weekend. The 450 motor is absolutely unreal, best described as a tractor. Suspension was a little soft feeling at trail speed but when pace picked up suspension felt alittle stiffer. Soaked up everything I could throw at it without a clitch in stock form. The 250 feels like a 125 compared to the 450. Where the 450 would soak through the bumps, the 250 would get on top and dance over it. After quite a few miles on the 450 I was ready to get rid of my new 02 CR 250. After switching back to the 250 and putting more miles on it, then back to the 450, I think I will stay on the 250. The 450 was fantastic, weight could be felt in the handlebars(made me more tired), It took tight trails with ease, most corners 3rd or 4th and just chugged along. The 250 is equally as impressive, not much for low end but it flat goes, the lightness could be felt over the rough stuff,what the 250 would skim across, the 450 would drop into. If I was going to buy again I would have to seriously consider the 450, but for now I am glad I have the 250. I am a OT int at about 220 lbs. All the riding was done on local whooped out trails, from sand to hard packed. Will try to wrestle the 450 back from the owner at a MX track for that type of comparison.