I have a mid 2014 Model S bought CPO that I've had for close to half a year now. The pano creaks/rattles a little on rare occasion when driving over just the right road surfacing to trigger it. Also, the passenger side has a rattle when radio is turned up (seems to be coming from door panel but I haven't really diagnosed it yet). I'm thinking of trying to fix the radio rattle (probably myself unless it appears it would require doing something that would risk voiding the warranty), but the pano doesn't happen often enough for me to care. Oh, I also have the occasional seat squeak from rubbing the center console on bumpy roads, but this is such a nit pick that I don't consider it a relevant issue to be addressed (only mention it because I've seen at least one thread on it before where someone wasn't satisfied with it).
You know, now that I think about it, I've heard people say that with the Model 3 people won't accept some of the eccentricities or imperfections that sometimes exist with the Model S. But I think really it goes both ways a little. I've also seen some folks who expect absolute perfection on a Model S because it is an expensive car, whereas someone buying a less expensive car might not nit pick as much over every little minor quirk. I come from the poor boy crowd that has never owned a Mercedes, Jaguar, or any other expensive luxury brand, and I seem to be far more forgiving than some of the folks who are more used to those types of cars. The less well to do crowd may expect to not have problems with things like door alignment causing problems with opening and closing, but they also won't expect free "repairs" every time their seat makes a squeaky sound.