We bought a Arctic Cat 500 with a dump bed in 2002, It froze up at 11,000 miles in about 2007, so I have no idea the miles now, but it still runs good. I expect it has over 20,000. We broke the wheel off the axle in about 2009, but had it repaired and it was running good until about a year or so ago when it stopped at the top after climbing a steep hill. I figured it was done for, but took it in and had it looked at. They blew the dirt out it, and it is running great again. I don't know anything about engines, so I am not sure what it was they cleaned. He could have really taken us on the deal, but it was an inexpensive fix. We also have a small Arctic Cat 300 we purchased in 2005. It is mostly used to spray weeds and pull a small spreader, so it only has about 8000 miles on it. We keep it at the Feed barn, so when we go down in the big side by side we have something to use when we go somewhere steep or muddy.
In 2010 we bought our first side by side, a Polaris 450 with the dump bed. It had a broken spring within the first month and seemed to be broke down almost as much as it ran. We traded it for a new Kubota UTV 900 in 2012. It is not something you would want to do much off road on, but it can haul a huge amount of weight. It runs slow and steady like a tractor. It has a lot of power, but it has to be on solid ground. I have used it to pull my neighbors F350 out of the mud. We haul feed between the barn by the house to a feeder barn a few miles out in the middle of the ranch. It has almost 800 hours now. It does not have an odometer. We still use the old 500 or the 300 when we are doing much off road, checking cows. We learned our lesson when we got the Kubota stuck within the first few days we owned it in a spot that would not have been a problem for the ATV's. It weighs more than my car. We got it out by building a corduroy road out of a bunch of old fence posts, and got it started by pulling with the 500 while rocking it.