My family belonged to one when I was a kid, though not in Vermont, or anywhere near it. I know quite a few people who belong to various clubs.
People generally seem happy with them, and the price is obviously right (relative to the alternatives). I'm not sure I'm coming up with a lot of positives and negatives that you haven't figured out on your own. There seem to a variety of arrangements, from those where each family has their own dedicated room to full-on dorms with rows of bunk beds. The former has the advantages of a condo, like being able to leave your stuff there, at a much nicer price. The latter should have a that-much-even-nicer price, though there's the risk it'll turn out to be nightmare (or what would be a nightmare, if you were capable of falling asleep with a party going on around you).
I suppose the big, albeit obvious, variable that'll determine how much you enjoy a particular club isn't so much whether the dishwasher is industrial-size, as how well you get along with the other members. There are, of course, two variables involved:
- You, and
- The other members.
Not much you can do about the former. The more relaxed and gregarious you and your family members are, the better. Teenagers have a tendency not to be: certainly not with adults or younger children, and with other teenagers at best unpredictably, and at worst with the sort of volatility that can (depending on which way thinks go askew) breed violence or grandchildren. Okay, I'm being a bit dire. The most likely downside is inexplicable truculence.
As for the other members, the general "personality" of different clubs probably varies in identifiable ways. Your due diligence should probably encompass a little bit of talking to members and -- to the extent your sense of etiquette allows -- talking about members behind their backs.