I have an Arctic Cat 375 that I bought used.  The only thing I wish was different was I would like fuel injection.  I have to stick a glove in the air intake to get it started if the temp gets below about 25 above.

I feel most operations don't need as big a machine as the sales people want to sell you.  A 400 or 500 is plenty big for almost anything.  4 wheel drive is a necessity however.