I'm getting interested in writing some Tivo box to video client(s) software and aside from the Tivo model I have, I predict it must be difficult when tracking down bugs on a model the programmer does not have. I wanted to see what other developers might already be doing for their testing. I wouldn't mind buying a Series 3, 4, 5 and Mini for development (because I could sell them for small loss eventually), but I do mind paying monthly service on 4 machines for something I'm not actually using. For mobile devs, there are phone farms companies can rent or even access remotely. I don't know if that's useful for Tivo or overkill.