I have run Yamaha, Polaris, Honda,and Suzuki. I average about 5,000 miles a summer on my 4 wheelers. IMO you can't go wrong with Yamaha or Honda. The one most prone to break down is Polaris. I run a black bear camp and most of my hunters (about 35 a season) bring up 4 wheelers. Polaris is the 4 wheeler I see most go home in need of mechanical assistance, in fact I would say over half of them have some kind of a break down during the week. For your needs I would go with either a Honda Forman, or a Yamaha Kodiak. Both great bikes with pleanty of features.
Just my opinion.