I am adding a new zone to an existing multizone setup. This will be a zone connected to a home theater receiver, to allow the home theater speakers to be used as a Sonos zone when the TV is not in use. The consultant I am working with has spec'ed a Sonos Connect for this setup. I have an old ZP80 that I am not currently using. Can I put that in, instead of buying a Connect? The rest of the system uses ZP90's connected to amps and ZP100s connected directly to speakers. Also, if I use the 80s and 100s in my system, will I have any compatibility issues if I want to add new units later, such as SUBs or PLAY:1 (or :3 or :5)? Thanks for your help.