Micomsoft XCAPTURE-1 is probably the best currently available. Avoid Avermedia, their stuff is known to be glitchy and problematic. Elgato gear is all USB 2.0, and will have about a 2 second capture delay which makes syncing your mic/webcam a bit annoying, especially if you swap between on-system and captured gaming.
As a note, the only reason to use a capture card is if you plan to stream a game from a console (PS4, WiiU, XBone, etc). If you're playing on-system, Game/Window(/Monitor) capture are going to be much faster, and a capture device won't offload any CPU/GPU load, and will actually raise overhead.