I love my HDHomeRun Prime. The only real issue has been my M-CARD stalling periodically resulting in a "subscription required" message on channels I am authorized to receive. I eventually set-up a scheduled task in Windows 7 on one of my PCs to restart the CableCard once a day (4 AM). Since then I have not experience any issues.
Frankly most of the issues I have encountered are Windows Media Center related and SilconDust's user's forum as a FAQ that covers most of these. »www.silicondust.com/forum/viewforum.php?f=43