One question: what is your audio source?
The DVD. My secondary source for when the sound quality gets too low is the SE LD. Actually there are still a couple of lines I'd like to replace, although it's quite a tedious process. Hooking up the LD and RF decoder, recording the AC3 via a SPDIF-USB box, decoding it (assuming the recording was good - occassionally it loses data. When I did my SE LD edit, two out of three recordings of the AC3 data were broken in at least one place), and pasting it into place. Besides I expect there'll be yet another "this is the only one" edition in a few years which will hopefully have better audio.
On the video side of things, I did consider trying to use a GOP editor but decided it wasn't worth the trouble.
ADM, PM or email me if you'd like some help making a crawl or doing some soft wipes.
David