I'm looking at picking up possibly the MX500 to replace the pile of remotes on the table. My question is this - how easy is it to set up the remote for multiple Tivos. I have different addresses for each unit for the Tivo remotes. Can I basically keep the same setup with the MX500? I have one ATT and two Phillips Tivos in addition to the Onkyo receiver, DVD player, Toshiba TV and VCR. I was curious about the ability to control multiple Tivos and ease of programmability for such. Would I have to program every single button for each Tivo? Or could I merely change the address in the MX500 remote and only teach it one set of Tivo buttons?

You will need to teach it every command from each tivo remote. You can't use the preprogrammed code, it being the default code, it will control every tivo at the same time.