I don't know that the sound difference between an ATV and UTV are really going to effect much. I have an 02 Rancher, it's as loud as most fourwheelers out there. I'll be more concerned with a comfortable ride with the next wheeler I get. I would like to have Independent suspension.
Recently I've been using my grandfather-in-laws new Honda Pioneer 1000. It's Way more comfortable then a 4wheeler, but not near as maneuverable once you get off of a trail. I haven't noticed much of a sound difference.
