I use 3 Dish Network Set Top Boxes. The 2 main ones are controlled by a USB-UIRT. And the 3rd is also controlled by an additional USB-UIRT in another room of my house. If I had the PCI slots available to me, they would all be controlled by a single USB-UIRT, but the dual STB MD only had enough PCI slots for 2 tuner cards. I have played with the Idea of 2 pvr500 cards, on my core, and switching back to a single USB-UIRT to control it, but that 2nd USB-UIRT also contols a VCR and a Roku Netflixplayer. However if all of these were in the same location, I could do it with only one USB-UIRT.
I have no experience with the GC100, but I am sure they are more than capable of doing it and about twice the price of a USB-UIRT.
If you do decide to go with the USB-UIRT, and install an i386 MD or core, please go and get my fixed module to allow the USB-UIRT to blast w/out dongles. It is here -
http://wiki.linuxmce.com/index.php/USB-UIRT_x86_FixJust go ahead and grab the module, and follow the instructions on the wiki as to where to copy it to. My USB-UIRT has a very powerful transmitter, I bought the one with the 56k ir bits in it. If I open up the french doors into my family room from the living room, it can blast across 2 rooms to control the tv connected there. But for accuracy and dependability, I bought a 2nd one for the room.
My experience with the USB-UIRT has been exceptional. They were in fact the best pieces I have purchased for my current installation.
Welcome, and Regards,
Seth