I just thought I'd throw this out there. When I first used Bandicam it was on my SSD and I was able to record my games fairly well with decent bit rate in HD.
After My laptop was repaired from RMA and had to rma my SSD as well (so using a normal HDD atm), I tried using bandicam and the performance just isn't as good. I have to lower the bit rate or quality so my game gets higher fps during recording.
It seems the best results would be to have your game played on an SSD and put your bandicam output folder on a 2nd hardrive to avoid read/write limits. If you think about it, running the game, with windows running in the background and recording on 1 hardrive just isn't going to cut it.
This may or may not be new or useful but like I said, just throwing it out there.