I totally understand the need for community -- that was why we joined a couple of years ago. But one year was enough. I don't regret having tried it or that year-- I did meet some nice moms but as others have said, that didn't translate into anything outside of class day, which was fine.
But, as the year progressed I found myself becoming more philosophically opposed to memorization without accompanying education. And since parents have to sit in on the classes all of the time, by February I was ready to poke my eyes out :) It is true I could have tried to match our work at home to the curriculum to provide the accompanying education, but it seems like that would lead to a fairly jumpy curriculum with little flow/coherence, as well as being a ton of work. And I like choosing my own curriculum.
SInce we only listened to the cds in the car to learn the memory work (and by spring even that didn't get done too much-- we were all tired of it) I felt like not being "all in" was putting at least one of my kids at a disadvantage as the year progressed. Her tutor was very rewards oriented for memory work, behavior, etc. I became concerned that my daughter would start feeling like she wasn't smart since some of the kids (who practiced the memory work regularly at home) clearly knew the material much better. (My daughter did retain an amazing amount based on how little we reviewed -- not sure if she still knows any of it though!)
So just some thoughts, but I agree with what others have said, do what you think is best for you and your family!