Destrekor mentioned some solutions that might be viable alternatives. I admit though I haven't had a chance to check them out. I own a Channel Master dvr for the downstairs tv and it does work really well. I love it. Your right there is no fee like Tivo but it comes with a heftier price tag.
I'm going to check some of those. My original intent with the system was a full media center with Blu-Ray ISO playback off a storage server. But I realized I don't watch movies and on the rare occasion I do I can use Apple TV or Roku or just a regular Blu-Ray player. So all I need is a OTA DVR solution.
As for Channel Master I'm glad it works well, and I don't mind paying more to avoid being dinged monthly. I don't need wireless as my setup is fully wired. My concern would be the quality of guide data and continued support for that data. If they stop providing that data then I suppose it becomes a $250 paperweight.
It would be great to switch to it and retire the Mac Mini and sell it to someone who can make better use of it.
EDIT: Wow! Great reviews on Amazon. The allure of the HD Home Run setup is that in theory I can use it on any Windows computer in the apartment however in the 6 years I've used it I've never used it that way. I tried a few iOS and Android apps and they don't really work all that well.
Also found this in a review:
"January, this year (2015), at the Las Vegas CES show, Channel Master announced an additional feature that will be added to the DVR+ platform, Linear TV. This will be in the form of a free update download for the DVR+ in the near future (early 2015 - last I heard, March). Linear TV, or "over-the-top" (OTT) TV, is basically live cable channels (WGN, CNN, etc) and some recorded "looped" content that is available on the Internet through streaming technology. Many free channels will be added (Internet connection mandatory to receive this programming). These channels will be in the same Rovi/DVR+ guide as the over the air channels and current Internet channels (Vudu, YouTube, Pandora). All the channels were not announced (work in progress) but many are promised! For more info and some of the additional cable channels to be added Google "Channel Master Linear TV"."
Think I'll have to order this. However, if an Apple or Google gets into this space I think it will be no contest. Xbox one actually is in this space but just in Europe - unfortunately. If they released a US OTA adapter I might turn the thing on every once in a while.