I have an 02',05',13' YZ250's
Bought the 05' first, in 2008, previous owner put SSS forks off of a yz450f on it before I bought it. I had the shock and forks serviced and revalved, I have rode the crap out of this bike for years and it has been super reliable. I love it. I bought a very clean 13' to replace it at some point. The 13' has never rode quite as well as the 05' (same setup) and the motor has felt a little softer through the entire range. An 02' came up cheap on local craigslist, it was a little tired and looked somewhat beat but it was cheap by local standards ($600). I fixed it up with new tires, plastic, torn it down and greased all the bearings blah, blah,blah. it rides like a total pile of crap compared to the 05' I was/am super disappointed. Although it looks great and everything is in good to great condition it feels totally clapped out compared to the 05. On the 02' I don't feel like the motor transmits the power to the ground as efficiently and you can feel the frame flexing when the track gets really rough. I recommend finding a clean 06' to 10' for the best performance at the lowest cost.