I'm confused by this. If you had a particularly good IDE in a particular OS, why wouldn't you use a VM and run that OS for the purpose of the IDE? Especially if its on Linux.
Visual Studio works great on cross platform code bases. It is so much better than Eclipse, but I'll stick with vim :)
Plus, if you're looking to build a cross platform GUI app, Qt is a great toolkit, and Qt Creator (as the name suggests) supports drag&drop UI building, QML etc.
I find that compilation in Qt Creator is possibly slower if you are on windows (using mingw) but on Linux its around 10 times faster (through the use of ccache and make -g4).
And the documentation is awful. I still haven't figured out how to make precompiled headers work with clang (but that may be my fault).
There is a relatively new clang based vim plugin that I haven't tried yet. Using clang to parse C++ into an AST is the right approach, so it sounds promising.
When people rave about Visual Studio, they are mostly talking about C# development. And even there, they often talk about Resharper.
That said, install Visual Assist X and Visual Studio becomes quite a decent C++ IDE. That does not fix debugging or the compiler of course, but refactoring, highlighting, code navigation, contextual cues and auto completion are mightily improved.
Contrary to many in FOSS think, all C and C++ compiler vendors have language extensions and gcc is not immune to this.