For low light, you can't beat DSLR. I wrote a couple blogs about the subject, one on the pros and the other on the cons, of shooting DSLR. I had them peer-reviewed. Check them out.
The problem with tight location, for DSLR, is crop factor. To be honest, I'm not sure how DSLR compares to camcorders, as far as shooting in tight quarters is concerned. Perhaps someone else will step in and answer that?