I have run BIAB in Parallels with windows XP and Windows 7 on Parallels (including Parallels 11, even though I'm now at version 12) for many years without problems. I have no external devices, though (no external midi or USB devices which must work with BIAB), and only for playback purposes (i.e. not using RealBand or recorded any midi or audio in BIAB).

Last year I switched to the MAC version, but that was just because I was fed up with Windows Update, and the Mac version is nowadays (almost) equal in terms of functionality.

/Björn