Pros
If your brain fits at Michigan Tech, it can be a fantastic place. My partner's on the faculty in a STEM field, and it's been amazing for him. There's a kind of joy on campus having this many nerds in one place - I'll always remember the time I walked into Walmart and overheard "EVERY idiot knows [insert differential equation talk here.]" Tech's smaller size means more opportunities for collaboration and (sometimes) less red tape. It also makes the administration seem more accessible - I've worked at larger universities, and I wouldn't think to refer to the upper-level administration by first name. Not out of formality, just unfamiliarity. At Tech, Rick calls Jackie to figure out how to fill Bonnie's retirement vacancy. The snow's a pro and a con. If you like getting outside, there are infinite places to explore. I've gotten in better shape since we moved here, since I picked up cross country skiing as something to do.
Cons
The downside of the smaller size can mean tendencies towards cliques, and university-wide decisions being made with little transparency and not much permanence. It's hard to love a large committee, but you miss them after the tenth "well, [X and Y names] decided [drastic policy change], so now we have to scramble." It's common for decisions and promotions to be made based on personal relationships. If you're connected to that upper-level club, you'll be fine. If you're a local and know the backstory of half of the employees, you'll also probably be fine. If you're on your own, you're on your own. Women and minorities may face problems that are hard to put your finger on, but just...don't feel right. Missed promotions, people talking over you in meetings, less lab space, and additional work without recognition or reward. And the downside of the snow. The airport only flies out successfully about 50% of the time in the winter. The days in February and March can be very long, grey, and cold.