A test of DVR tuners would be great but unfortunately it is a niche market and the equipment required to do such a test would need to be quite sophisticated.
I've experimented with 3 different antenna DVR products:
Bell 9242 HD DVR Satellite receiver (with an antenna input)
MyGica 586 Android Box with an antenna input
Silicon Dust Homerun Connect HD (Dual channel tuner)
I would say all three tuners were amazingly equal despite the differences in technology of the various devices. There was almost no difference in the number of channels each device could tune. All 3 options would work for different people depending on their TV view habits and expectations.
The biggest difference was the features each device had.
Overall the HD Homerun would be my first choice for a hobbyist largely because of the channel diagnostic features built into the device and the huge amount of flexible viewing and IP streaming options (think OTA TV on your smart phone) as well as DVR options. When you combine an HD homerun with a computer running windows media center you get a system that rivals a standard cable DVR set top box.
Full media and channel guide for all OTA stations in your area
Live TV pausing
Multiple TV's supported with Windows extenders
Alas windows media player never took off and windows has basically orphaned it (the TV guide still works though). You need a computer that runs Windows 7 and you have to go on Ebay to get an extender (Dlink DSM750 or Xbox360)