I do have an HTPC and use it quite successfully with everything except satellite tv. I still maintain that's the complicated and expensive part. The capture card isn't bad, but you need a massive hard drive and serious processor to go with it. Add to that a wireless keyboard and mouse. Then you have to control a satellite box via IR and can only access 1 HD tuner per box, so you save nothing money wise by the time you get a second tuner. Stand-alone DVR is much cheaper and easier IMO.
That's because you're using a htpc with a satellite box. The vast majority of people use them with ota/cable. That's what they really are designed for.