I personally like OBS the most for my game dev endeavors. Even for streaming and recording gameplay. Its really come in handy. Some of you probably saw it in my asset vids. Its free, opensource, what more could you ask? I tried Bandicam, and Fraps too, but they aren't free and didn't get very good results with them. Fraps is really smooth if you have the hdd space to record uncompressed, but I don't.