I haven't used a camcorder so to speak, but I have captured/edited video from my VHS tapes through the composite-in from my VCR and a fair amount of capture/editing from the tuner. You understand it is not a digital video solution for capture, it's an analog capture device. I've been very happy with the capture/editing(I use Adobe Premiere 6.0 for editing primarily), and as soon as I get my S-VHS recorder(to make use of the higher quality s-video input) I'll convert my VHS to SVCD's(hopefully Nero's internal mpeg-2 compressor will be ready by then).
ATI's new DV Wonder loks interesting for digital video, but I don't know much about it yet other than it offers firewire ports.
I use my rig for gaming as well, haven't felt I gave up any 3D performance yet.