So far I'm having trouble with the AHviewer replaying with a lot of hitching and such when trying to record using FRAPS. I set my resolution down to 1280x1024 in order to lessen the burden on the machine (I normally play at 1920x1200) and told Fraps to only record 1/2 of the resolution.
My machine uses an Athlon64 X2 4400, and a Geforce 8800gtx, with 3gb of RAM, so it's not like it's a slouch or anything.
Since no application can use more than 2gb of RAM at once, I set up a 400mb ram disk and set Fraps to write to the ram disk in order to eliminate one possible reason for the hitching.
I'm still getting hitching during playback, which shows up in the Fraps video.
One thing that might have something to do with it is that I have never gotten any of the "multi-core AMD cpu bug" fixes to work, other than setting AHII and AHfilm viewer to Win98/ME compatibility mode. I play the game just fine this way. I really wish, though, that I could get AHII playing properly, without the spinning clipboard problem, without being in Win98 compat mode. I'm totally losing out on multi-threaded benefits.