I keep hoping that performance issues get addressed, but they keep getting worse with every EAP. The main culprit seems to be some background checking, in the status bar I see:
'checking com.foo.bar.Whatever' while editing a completely unrelated file. Once it's decided to check something, it'll keep checking it over and over, every few keystrokes (including moving the cursor). Only way to stop the check is to restart.
Is anyone else experiencing this? I'm at the point where I avoid opening or editing certain large classes because I know that IDEA will decide to check them for all subsequent edits of any file.