Excellent work. I like to ignore visual studio completely and pretend it doesn't exist, but that's just me :)
I've used cygwin's cross-compiler x86_64-w64-mingw32-clang package once in a while, though I find more projects' build systems choke on it and do the wrong thing (libgmp as a notable example) than with x86_64-w64-mingw32-gcc.