[faboo]

I'd second ViEmu. The price is a little steep (or was three or four years ago), but I used it through the trial and it was pretty comfortable.

These days I do a lot of my C# coding in Visual Studio, but have a shortcut key to open the current file in GVim to do heavy lifting. For what it's worth, to do that, I added gvim as an external tool with the arguments:

--servername "$(SolutionFileName)" --remote-silent +$(CurLine) "$(ItemPath)"

Which keeps all the files you open from a given solution in the same GVim instance (nice if you edit multiple solutions at once).