Wow, this is timely... I just saw in the bookstore today the new issue of Cycle World magazine. Jimmy Lewis wrote a story about comparing the best 125 class bike (250F), the best 250 (YZ250) and the best four stroke (CRF450). They said the 250F was the funnest bike to ride so if you're just riding for the fun of it and not racing then that's the way to go. As far as racing they said at the pro level the YZ250 has a slight advantage over the CRF. There were many downsides to the YZ250 however... harsh suspension, more tiring to ride and a lot more skill required to go fast on it compared to the CRF. They ended up picking the CRF best all around. It's a really good story, informative, objective, and not biased... typical Jimmy Lewis.