Years ago I belonged to one and found that it wasn't for me. Too much was stuff I would not use. At the time I also had Archivers so I could get my stuff pretty easy.
I subscribe to Kitaholic Kits. They are put together very nicely and suit my style of scrapping. I also get every second Colour Blast kit.... I'm on their DT. I love the uniqueness and the mixed media with these kits.