i'd probably try to take a look at the dm as much as you can. a good dm can pull a bad group together. my current dm has been a close friend for the better part of 20 years so it wasn't a huge risk for me but one of the players specifically and i had a couple of issues early on. basically it came down to "this is what my character would do" type nonsense, though in retrospect it was 100% what his character would have done. i talked to the DM in private, things were smoothed over and, like i said, we've been playing weekly for just about 4 years without further incident.
right when we started, the DM had written down his basic rules (he started doing some freelance dm'ing for groups that he didn't really know well so he made, basically a list of expectations). i was a LITTLE hand wavey about it at first, but ultimately it's been a big help in a lot of situations. his thing is basically that d&d is a social contract between all the players, including the DM and the point is for EVERYONE to have fun. as soon as it stops being fun, people start leaving. and as soon as YOU start having fun at someone else's expense? YOU'RE leaving.
he was very clear with what he expected from his players, and he was clear with what his players should expect from him. i think that, in and of itself, can really set the stage for what kind of stability the group is going to have. the games i've had that HAVEN'T had that clear, haven't stayed together. if you're thinking about contacting a group to join, i'd talk to the DM first just to get an idea of what kind of game they are running, and how they handle interparty/interplayer problems.
edit: one thing about the "everyone has fun" thing... we do tourney's every year now, where basically it's a weekend full of 3 hour one-shots. there are a couple of dm's and like 2 teams of 5 and we play one day with one dm, then the next with the other. it's fun but the loot system that the dm's put together was compeltely rng and we had like, 2 people get consistently awesome loot and 2 people get consistently terrible loot. every body was gracious and we all had fun overall but a few of us had a long conversation with the DM's about the loot and had sort of a constructive feedback session. one of the guys (who ended up with like, 20g and a standard healing potion as a reward) was like, yeah, i get it, i know why you did this, i know it's all based on roles. we all like roling, it feels like our fate is in our hands... but, it wasn't fun. it just wasn't fun.
the dm, who had been pretty adamant about things up until that point turned an immediate 180. you're right. you're 100% right and i'll start working on a new system for next year immediately.