I'm going to continue to use my HD PVR 2 over the internal DVR the Xbox one has because the PVR can record 1080p and stream with no stress on the console.

If you are recording while playing using the built-in dvr it may impact the game, I'd rather use my PVR which is much much easier to use to record, stream, upload with in full 1080p.

The new software Hauppauge Capture is fantastic too. (Can be found here for more info by the way http://www.hauppauge.com/capture/ )

Hauppauge provide great support too so there is nothing pointing me away from continuing using my HD PVR 2 with the next gen console.