Have you considered a 50" SXS? There aren't many models on the market but they do have advantages. Besides 2 seats, they have more 'trunk' room. They'll climb as well as an ATV although they aren't as good on steep sidehills because you can't stand on 1 footpeg. However, the weight is lower so that balances it out somewhat.
They're about the same width as an ATV but a little longer.
We have a 2016 Polaris RZR 800 which is a 50". I've taken it some scary places. The only problem I've had was a plugged oil pressure relief valve. They said that was a very unusual problem.
