Very true. I was pretty worried when I posted my first story (Teen Titans), and it wasn't until I got a number of good reviews did I decide to continue it. Of course, one of the reasons why such a group exist is so that they could improve, and of course, I'm sure to get positive feedback from readers. However, again, IMO, they are not that great as of yet.
And if asked, I wouldn't join it since, well, I work alone for the most part. I of course post previews here and at Shinjis, and my biggest story even has a Beta reader, but still, for the most part, I work alone.
That being said, as I cared more about qaulity, well, time between updates have been lengthened. Hehehe. Well, guess I can't have both huh? <_<