I am using QtCreator on Windows.
It is great, but I wish it had better CMake support.
It does have VIM emu mode, but I haven't tried it myself.
I don't use KDevelop projects on Linux, but instead work with the CMake scripts directly. Not surprisingly, KDevelop's CMake support is top-notch.
What I miss from KDevelop is the excellent CMake support as QtCreator often fails to deliver 'intelli-sense' when it's not using qmake projects..
I, too, use Qt Creator (with GCC) on Windows. While I think it is a pretty good IDE in its own right, what I absolutely *LOVE* is a component that's under the hood -- namely, the Qt Build Suite. It is powerful, flexible, easy to use, and integrates seamlessly with the IDE - while Qt Creator supports CMake (which I like and have a lot of respect for), the Qbs integration is much more polished.
While Qt Creator is my IDE of choice, I also like VS2013 -- and I just can't go back to using a standalone editor for serious work anymore.