Over the Air Content
HDHomeRun
We are using a HDHomeRun Dual for our ATSC source. The HDHomeRun allows me to keep the antenna in the attic, and the PC downstairs, without having to run a antenna drop down the several floors. It will also be possible for us to add an additonal HDHomeRun if we want to add extra tuners. The tuners on the HDHomeRun can also be used on other computers in the house, though I am not currently using that feature.
My recommendation for anyone using an HDHomeRun is to use Gigabit Ethernet for the drop between the main network switch and the Media Center PC. When recording two 19Mbs ATSC streams, you will want to leave enough network bandwidth, so if anything is happening on you network, the video quality is not affected. For example, on our Media Center I want to make sure that I can record two shows, while the Media Center is backed up, movie that is stored on the Windows Home Server is being watched one the Media Center, and some recorded content from the Media Center is being watched on one of the Media Center Extenders.
I was seeing some degradation of video quality when using 100 Mb Ethernet, but haven't had a problem since upgrading to Gigabit Ethernet. I haven't upgrade my whole network to Gigabit, but that isn't a problem as most of the other devices can barely saturate a 100Mbs drop.