I had the TPMS light go off two days ago. It got down to 20 degrees (F). Checked the pressures and sure enough, the rears were both around 25 psi. I had them at about 30 with temps in the 80 degree range. Aired them up to 32 psi and no more light. System seems to work as intended. If the average driver truly understood the damage that can be done to tires when run underinflated, they would really appreciate this system. I will not argue that it is a PITA when dealing with winter / summer tires. I have seen protypes of TPMS sending units in the valve stem cap instead of mounted to the wheel itself. That would sure make moving from one set of tires to another much simpler. There would be a rash of thefts on valve stem caps though.