Any thoughts on using the AGC?
Yes, don't. 
Just set your levels low so there is no fear of clipping and massage the gain up to where you want it. Gotta use your ninja skills when you are that up front, but it can be done!
Well the only reason I asked and I understand if you throw something at me is....I bought the Edirol last year after using a Sony MD for many many many years. My mics are great and I love them but I don't love changing the volume. Out of 10 shows last year I still couldn't get the volume right. So I actually started using the MD again to avoid having to fiddle with volume when recording.
<sets rock down>

By volume you actually mean the gain control for the mics. For me, I like levels to peak around -6 dB to -3dB and I don't think that's a sure thing when using ACG. I believe ACG was developed for functions other than the live concert recordings that we do, so it really wasn't mean to suit our needs.
Manually setting the gain at the right level just takes practice and you'll be a pro before long. Obviously, it's tougher to do when you are front row and security may be on top of you, but it can be done.
I once recorded shoulder to shoulder with a county deputy and he had no idea what was going on and unknowingly was an excellent blocker. You gotta love the Barney Fife's.