dropping "native win32" (msvc) support

What do people think of dropping "native win32" (msvc) support?
Personally, i can't test (although i do detest :-D) it -- haven't
touched a usloth OS for 18 years.

IIUC, cygwin and mingw are by now mature enough to provide reasonable
(less work) portability targets.  This impression is from a quick scan
of the cygwin API:

  http://cygwin.com/cygwin-api/compatibility.html#std-susv4

but i don't know for sure (as above, i don't have any way of testing
either of these platforms).