I have Windows 8.1, FSX and PMDG (737-NGX and J41) Not a single problem to report at all. Works perfectly. I think the lesson we can all take from this is; Does what you have, hardware and software wise do what you want it to do? If the answer is yes, then whether you are running Win 7 or Win 8, is irrelevant. It works, and you can go flying.