It's the only VIM emulation mode I've used that isn't completely annoying. I'm including spacemacs in that assessment.

I agree, it's just Good Enough. I mostly miss some add-ons like surround.

Surround support was just added in IdeaVim 0.46. From the release notes:

Support for vim-surround commands ys, cs, ds, S, enable it with set surround in your ~/.ideavimrc

:-o Thanks!

It's OK but I could never get it to do things beyond basic editing like window management right.

It's high quality as they go but not close to being a vim substitute in my experience. There are still tons of little things that don't work as expected.

so is netbeans's - it's a straight port of the vim source code to java