Mr Murphy, I'm not trying to bust your biscuits but should/can a bicycle of any kind be compared to an ATV or SxS? Wouldn't a more fair comparison be the benefits of biking over walking?
I guess the word "better" is subjective and conditional. Up till a few years back I didn't own an ATV. On hunting trips I drove my truck to walk in trails and humped it in from there. There were some places I wouldn't take my truck. 20+ miles up a mountain range and very bad "roads" limited my access to a lot of locations. So I got a 4wheeler and mounted a good rifle case on the front & big lock box on the back for inserting myself into harder to get to places. My last elk hunt the conditions were so bad that I had a rough time just driving on constituted dirt roads in my Ram 2500 w/new 35" mud tires and chains. Even my 500 Sportsman was severely handicapped in 4wd. My buddy's Ranger plowed right on like it was nothing, most of the time in 2wd. I'm currently looking for one now.
Learned a lesson that trip; if the locals aren't going into certain areas, may be for a good reason!