My wife has a Mercedes GLK350 (now called the GLC, because of their renaming), which is a little more SUV than CUV, but it's based on the C-Class chassis. Overall, it's really nice, for a crossover, but I'm not that big of a fan of them, to begin with. We looked at the ML, which would be out of your price range, and it was MUCH nicer. The 3.5L V6 is strong and pulls hard, and while mine is RWD, the AWD versions have basically the same system as the C-Class, which my wife had prior to this one. It handled GREAT in the snow and rain, but since we live in SC now, there was no point in spending the extra coin. Oh, they also offer a Bluetec diesel, which I would have purchased, had they had one in stock.
That said, the GLK350/GLC300 will be a little more than $40k (I just kitted one out with NAV and an exterior styling package with RWD at $47k), but they're great vehicles. You could probably pick up a leftover or a CPO for less than $40k. Maintenance can be a little pricey, but we usually just roll a maintenance package into our lease for like $8/month.
2016 Race Red GT Premium Fastback - Performance Package, Navigation, Enhanced Security Package, Ebony Premier Trim