I have my old HR10-250 in my son's room that he has been bugging me to upgrade so that he can get the new HD channels. I upgraded to an HR20 for my family room back in January and have been quite happy with it. My only issue is that it is inside a cabinet and generates quite a bit of heat. I called Directv today and they offered me the $99 swap for a new HD DVR. My only question is do I want a 20 or 21? From what I have read the 21 is the same as the 20 except it is black, has a little more storage, does not have VOD yet, runs a little cooler due to an internal fan and lacks OTA antenna's. It seems like that is my best option since I get all the locals here in South Florida thru DTV. I also have read that the HR-21 might get future OTA thru USB but I am not sure how that will work since I use coax now. And apparently VOD is in the future also. So is the HR21 the DVR of choice if OTA is not a necessity?