I think the only caveat is that some file-updates are not backward compatible. e.g.: Once you open a document in RW 7.1+ you cannot open in an earlier version of the app.
There are a few of these points here and there. Best rule-of-thumb is always move forward. In the rare case you need to go backward, use TimeMachine backup.
Interestingly, it looks as though I can’t do what I’ve described above. Sounds as though RW7 will automatically copy all of my add ons and plugins across whether I want it to or not?
@robbeattie - i think it does that, but you can just uninstall things you don’t need. you are the master of your RW universe!
i think, far and away, the best version of RW 7 is the very latest 7.2 beta. i would definitely skip 7.1 and go straight to that one. even though it’s a beta, it fixed several important data-loss bugs which seems well worth running the beta if you ask me.