I tried it with only one tuner and I could get some stations. Later when I have more time, I will try to see if I can get all stations working.
First, I chose the tuner that is connected to my antenna/8VSB and then clicked on digital to scan channels. It didn't seem to find any channels until I ran the HDHomeRun Config utility. When I stepped through the channels in the utility, it then found some channels, but not all. It also used different numbers than I get when using the HDHomeRun scan. This is probably because the stations don't display the correct numbers.
I'll try the tuner set to QAM, which is connected to my cable service later.