I use VIM pretty much exclusively now.
I used to use Vim for editing and VS Editor for debugging. This probably seems a bit crazy, but I found the Vi paradigm (macros, home key based editing etc) such a boost to my productivity, that editing in VS was paintful.
Thanks to Viemu, I don't even have to do the switching any more. It is not the perfect solution yet (code completion is sometimes not as elegant as in native vim and the macro recording isn't perfect), but it is much better than switching back and forth constantly.
The learning curve for Vim is probably exaggerated. I think once you get into it, it is pretty intuitive.