Well... I've been using C-band as my primary entertainment source for about 25 years now. The advantage of C-band 4DTV is you can get your programming a la carte; i.e. you only pay for the channels you actually watch. The annual cost for us ends up being 25% or less of the cost of getting these same channels from either Dish or DirecTV. In addition, the bandwidth allocation on most of these channels is greater on C-band than DBS; i.e. better picture quality. Finally, I chose the HDD200 approach because it has been my experience that the HDD200 is far more reliable than the 4DTV receiver. By putting the USB interface in the HDD200, I can easily switch 4DTV receivers. I have two, so if one has to go in for service, I can simply switch to my backup receiver. No, the HDD200 R5000 interface taps into the primary data stream so you can record all broadcasts, both SD and HD.
The big downside to using the 4DTV receiver was there was no simple way to make scheduled recordings. I had to program the receiver and DVR separately and frequently messed up in one way or another. The R5000 / SageTV approach was a dream come true... that is if it worked reliably. Unfortunately it doesn't, and on shows I really don't want to miss, I still make standalone DVR recordings as a backup for when the SageTV approach fails.