I finally broke down and replaced my old, old Davis VP2 setup with a brand new, decked-out everything VP2 Plus - new ISS and console (yeah me!). I'm keeping the old ISS for parts and decided to use both consoles, but I'm getting different barometer readings on the two consoles. It's not a big difference - right now one has 30.06 and the other has 30.09, but it is irksome to me. Both have the same elevation and other settings, so the only thing I can think that might be the cause is a firmware difference. I might have updated the firmware once on the old Davis console when there was a Windows machine in the house, but don't know how long it has been.
Also, just FYI: I tried to plug my old data logger into the new console and received the message "Incompatible Logger" on the new console. No big deal, but I DID want to use my new console to connect to WC for grins and because it's shiny.