alright guys, i know this is a common thread but mine has a slight tweak. so i have a yz250 and i wish i had a quad, and im trying to sell or trade it off. mines a little rough and ill probably not get over 1500 for it. i have two cousins with 400exs for possible sale. one..he wants ~$2000 for it and has cam, powercore 4, beadlocks, axle, shocks, and maybe a few other things and is an 06. the other is an older one, possible straight trade has 20 over, cam, p & p, fmf ti 4, and geared..but is a little rough and no suspension work, so ill need to spend some on it. my other options, of course, are the z400/kfx or a 450. for the z's, i can get a stock to piped one for roughly 2 grand. same with older yfz 450s. now, i know the 400ex is the most reliable, and the 450 is the lightest and fastest. the z is generally the midway. i mainly ride my little track and my friends mx track, so i like to jump. ive read the z isnt the best jumper though, is that true? i also ride some trails, nothing super tight but have a few slow parts. i also want to start racing and want to beat my bro and friends...125 and 250f dirtbikes...so ill need some juice. when i went to my friends, i rode is piped 400ex and id consider us equal riders. hes at his home track, so he had the advantage, and i didnt wanna wipe his bike out. he basically spanked me. i dont like that! but, for the price and reliability, i like a 400ex. the z, i mainly like the speed and reverse. a 450, im just pushing the price a little. i also hate working on bikes. my past 2 bikes, ive dumped thousands in. so obviously, the 400 sounds the best, but i just want that power and jumping capability! how is the reliability on the z and 450s anyway? and which do you guys recomend??

p.s. sorry for the novel