Both are faster but depends on circumstance. if ye want to upload to say youtube, bandicam is the one u want. ye just wanna share .dem for reports on violation of a skial server then i believe ingame recording is faster. still gonna stick with bandicam though. i only need press one key (F3) and it instantly records to an avi of my preferred compression (yv12, xvid, etc).
and since youtube framerate limit is 30fps, i set the settings to record @ 30fps though it costs me to play in 30fps (whenever i feel like uploading to youtube of my ventures in skial's fortwars server, this becomes handy)