In my opinion, you need to ride and/or sit on each quad you are considering and buy what feels right to you. Try to find them together at a dealer. Trust me, you will know which one suits you just by sitting on them. Keep in mind, the Raptors are a little taller which makes them a little more tippy but you will gain reliability and have less maintenence, assuming you go by the book. The 450's recommend changing the freakin piston every 15 hours, at least that's what my 06 CRF450R manual says. Although, my engine has never been apart and I just had the local dealer check my valve adjustment and it was perfect. Not bad for 4 years old and raced. This ones a keeper. People I ride with include Yamaha and Honda 450's, bikes and quads. My son blew a Yamaha, his friend blew a Honda. They all have their issues.
Once you decide on a model, focus on condition. Try to find one that has been maintained well, hasn't been apart and doesn't need frequent valve adjustments. Are there bolts missing, loose or obviously not the right bolt? Excessive vibration? How does it steer and handle? Does it feel like it's been abused? You'll know the well maintained bike when you see it. There's my 2 cents...well, maybe 4.
