PL/SQL Developer has been having performance issues when many files / windows (in PL/SQL Developer) are opened. Memory used by PL/SQL Developer doesn't grow when opening more windows (according to task manager) which I wouldn't mind one bit as I have plenty of that.

BTW, I cant reproduce copy performance issues even with 20 files opened. One of the things I don't use is the Ribbon or Lint. (Never liked it, I have a wide screen monitor and it uses valuable vertical space. Also I can never find anything on the ribbon.). Don't think I have other settings that could improve this set...