I have the 266e in my 800 and I have absolutely no complaints. Just came from the oregon dunes and it seems fine to me. So the question would be horse power. For the intended use you described, a 266 is just fine. I you want more get -n-go, maybe a 345. I feel the 266 or the 304 is pretty well matched for the drivetrain on the 800 unless you want to go bigger there too.