Most likely the stock suspension on anything will have to be moded for a 300 pound rider.

Another thing to consider is that the Kawi is an automatic. Personally, I don't thing anything that is automatic is a true "sport" quad.

 

I agree on the suspension part.

As for the automatic, I once thought that way also. Until I rode with a Kawasaki 700. That thing ripped right along and didn't seem the least bit handicapped in comparison to all of the sport quads we were riding with.

 

When I'm sure a DS650 or 700 Raptor would be ok, I don't think you need something that big. I ride with a guy who is around 300 lb, not all muscular, but he only rides a 400 ex, used to ride a 300 ex. I don't live near any dunes, so we only ride coal mines and a bit of woods. I think a Honda or Suzuki 450 would be plenty large enough for you. Though like someone else said you have to take into consideration what you are riding WITH. If your buddies all have Raptors you won't necessarily want say Banshee,. and visa versa. I think a 450 would be fine for you.