Blackmagic Intensity Pro has HDMI in and out, so you don't need an HDMI splitter and there is no reduction of quality. And you can capture video from Intensity Pro using Blackmagic Media Express or freeware VirtualDub, so you don't have to buy any expensive software.

AverTV HD DVR and Blackmagic Intensity Pro use CPU to compress video (unless you want to save uncompressed video with the Intensity Pro).

If you want to spend as little as possible, get AverTV HD DVR. I suggest you to compare video recordings from both capture cards.