The critique group experience

I've just joined a writers' critique group. I don't think it's a great fit for me, but before I go shopping for something different, I thought I'd ask here.

Have you ever been part of a critique group? How about other writing groups (like beta partners, writers' organizations--places where you work on your writing "out loud" as it were, with other people)? What kinds of writerly interactions have helped you become a better writer? Finish something? Polish something? Has a critique group been valuable to you? In what way? Or in what way did it fail expectations?

I'd love to hear about it.

( Critique groups )