I am 6'6" 235 lbs + and have rode a lot of quads.
All of the except the DS650 seem WAY too small for me ......so that's what I bought.
Since you are a big guy, I would go DS650.
Just my 2 cents.

 

I believe you would like a ds, for the kind of riding we do in Iowa, the extra 3-5 in. of width mean nothing on the trails around here. I'm 6'2" 200 and I don't feel too comfy on anything except maybe a pred, but i"m so use to my ds it feels kind of wierd. PM me and maybe we can go riding, I'd like to have you're pred. riding bud smoke me, I 'd get a kick out of it. I'm only 1 1/2 hrs. from C.R.