No need to use preview inmy opinion, just check your video output after record
vsync is useless for actual gaming (aside from removing screen tearing), unless you like having input lag in most games. I would disable it since the capture method has nothing to do with your in game fps; it will pick the samples it needs from the game/window.
Anyway, how does 1080@60fps look from your video? can you provide samples on youtube? also, just curious, what card are you using?
Is there a way to disable the preview? I did mean during playback of the recording about vsync, I haven't found a player that will just play the 80fps video without vsync (players that I've tried will just skip the extra frames) under Win8 at least.
I always use vsync (and force triple buffering if possible through RadeonPro) I haven't noticed any significant input lag with my MX518 as long as the game is working properly. I'm using a 7950.
1080@60 does look smoother now than the video I originally posted, but it does still stutter from time to time. I'll post another video when I get a chance.