TPK-- It appears that you get a PCIe host adapter card to connect to the external device via a proprietary cable. Not sure how it works with HDCP, part of why I was asking if anyone had tried one.
I hadn't really thought of the SageTV aspect, but that may be an additional plus. My primary interest is transferring off TV shows, storing them on a NAS that I can use any Windows PC to play, or something like a Roku, as I know eventually my Uverse DVR will fail, or I'll want to switch to something else.
Appreciate all the suggestions, yea, a lot has changed in just a few years!