I liked fraps, but the file size was jumbo.. But if memory serves, it was the only one that I could use with Automobilita? I've tried most of them, other then the OBT software.. Anywhoo, I got Gforce Experience to save the replays now, but they save in multiple files if they're over 4 gig.. (8 lap race at Riverside in Assetto, with 16-17 cars is like 5 gigs. (so basically +/- 11 gig after the "incar" and "tv" replays) But I got it and it's currently "rendering".. Freakin 3 HOURS to render.
(Me thinks I'll change the settings if I do another one of this size.. lol)