In my opinion i would go with the polaris rzr or any ranger in the polaris lineup because i have heard a lot of good about them and not much bad. however i have heard of issues with arctic cat's reliability. Also with the sportsman xp850 u get a good looking, fast, quad that has best in class...
although i won't have the money for 3-4 months i am wondering what would be a good atv that would be low maintainance and cost no more than $2500 i have seen a few 400's for about that in the years 03-04 what do you think?