i have, and i'd say it was a positive experience for me, but not in the same way
it was a little bit like the scene in the movie about brad cohen, "front of the class", where brad goes to the tourette's support group with his mother, and they meet a variety of people with tourette's syndrome that have "let tourette's win" in that their parents had given up on them or pulled them out of school because it was too much hassle/they didn't believe in their child, and they were all unemployed and had no prospects. my experience with the autism support group has inspired me in much the same way as brad cohen was inspired by his experiences in that i now strive to be "better" than those i met at the group, and don't let autism hold me back. since then, i have won an engineering scholarship that required me to do interviews, and i have forced myself to take part in public speaking competitions in order to improve myself. i now make more of an effort than ever before to not only maintain my relationships, but to forge them.
from the way that you talk about it though, it sounds like your experience with the youth group was very different from mine.
even though the film is about tourette's and overcoming it, it is probably applicable to most neurological disorders, including autism/asperger's, and has certainly inspired me. i can't find the scene i'm referencing, but iirc the film is often shown on TV.