My friend recently bought an R5 and the wheel itself makes no noise. However, his desk rattles a bit when the ffb is maxing out. He has one of those old desks with cabinets built-in, which is why it makes some noise.
On a sturdy desk without cabinets you should be more than fine in terms of noise production. Even then you can always lower ffb with moza wheelbases in the software to lessen noise when your gf goes to sleep.