how often do you check the air in your tires? Are you keeping your tires at recommended PSI? Granted the Rial's are probably just can't handle the weight of the MS, but what I'm wondering is if your psi is always low, making the tire "softer" and thus more susceptible to allowing a pothole to pinch the tire inward enough to straight up dent and bend the rims.
.................. But like I said i'm very diligent about keeping them at exactly 45psi.
Considering RL's. Reading the thread, it is a given the MS weight and potholes are perhaps the biggest issues, but has anyone considered that running 45psi cold, or at least 48-50 pounds warm isn't doing these wheels any favors? Thinking "more pressure=less pinch flats", works to a point, but it also transfers more of the force to the wheel than by letting the tire absorb it, at lower air pressure. The point I'd suggest is that neither 21's, nor 19's, are suitable for the winter roads many are driving. They're both too close to the road surface. We're asking for these issues more than arriving at substantive quality differences, IMO. Too bad there's no way an 18" snow fits a Model S.