If it is listed as a USB device in your "Devices and Printers" it should be usable with the Aerofly RC 7.
So far anything I plugged into my USB ports as a joystick also worked in Aerofly RC 7. You could also try to search the forums (top right magnifier glass) and see if anything related to the Realflight controllers can be found.
When it doubt maybe try to find a person or local hobby shop that has the Aerofly running and test it there before purchasing it. If you buy Aerofly RC 7 via Steam I think you can return it easily within two hours of game time but I've never done something like that myself, users of the Aerofly FS 2 have reported that it is possible to do that via Steam. So read the paragraphs of your license before purchasing it, when you plan to immediately return Aerofly if your controller isn't working.
I hope that was useful, maybe admin can add more once he returns from vacation. Maybe drhotwing1 (IPACS) also knows something about this.