I am member of only one Group and I'm a contributor in another and that is just the perfect amount to keep track of the artworks coming in.
As a contributor I am surprised how practical it has become and it is more of a joint and collaborative effort than regular clubs. It's not perfect, but so far I think that there are more upsides to working in a Group.
I used to work in several clubs before the Groups system and it was a hell of a lot more work having to submit each and every submission that needed to be handled just as you submit a deviation in your own gallery, you know. So Groups are definitely a HUGE time save and so much more effective.
As for the member aspect of it, it is much easier to submit artworks now too.
i like groups. nice to help get my work seen, but i have almost 5,000 deviations between groups and individuals i watch over about a month, with me looking at some almost every day. no way i can look at that many.
Its the best thing that happened to dA since collections
really its a great way to sift through all the new artworks around dA without leaving my message center...and you can now feature your work and get real feedback, comments, favs...back at the old club system i bet hundreds faved ur work in the clubs galleries and not the original deviation