I use OBS (Open Broadcaster Software) it is free, highly customizable, can record live streams or directly to a flv/mp4 file, you can overlay video on video, record from multiple sources at the same time, records in HD up to 60fps, and records video through the GPU (just like shadowplay) so you get really high FPS while recording (I see a 2-5fps drop in UE4 compared to 20-30fps drop with FRAPS).
I highly recommend it, amazing little program. 