I think bad video is worse than no video for selling yourself. Even if the video is good the sound has to be good too or it just sux. You really have to do a multitrack off the board and mix it down in protools or some such later.
I had a portable 24 track for this but folks really don't want to pay what it costs for all that
. It's a lot cheaper to just do some demo audio tracks at a local studio. I really think it would a great sales tool for a band to have some well produced live audio or video but yah gotta pay the big $$$ for it. I was only looking to get $200 above the normal sound gig price to provide a 16 track recording on a 20gb hard drive (about 4 hours of capacity) but then you'd have to bring it to a mixdown studio - maybe $50 minimum a song for that?