Yama? Um, no. That motor's backwards and everyone that gets on them, falls off. it's like they started designing them, and never stopped. They should look back at the 07-08 YZ250f's and see what a good bike rode like. Or look at pretty much any Honda in the last 10 years.
I've raced on CR's and CRF's for decades. Excellent bikes. Are they the most powerful? Not usually, but a local level, they're all good. Hondas handle good and make you feel comfortable. If you're comfortable, you ride faster. Period. I switched in 07 to a KX450F and loved it. Wore it out and after trying some others, bought an 08 CRF450 for fun. It was great. Just like old times. Fast forward to this year, 2013 KX450F with CR high bars. Best bike ever. GOBS of power with the higher HP coupler in it, great suspension out of the box and just like old times, it feels like a Honda with more power. Just get one. It's not a lifelong commitment or a six year car loan. The Kawi's are mean, light and comfortable. The 2011's are a bit heavy, but basically same engine. If you don't like it, sell it and buy something else. They're just bikes, not children.