Failed after a month, poor internal soldering
This seat warmer worked wonderfully in gentle use for about a month, then failed.  The temperature control unit failed, displaying "99" instead of the set temperature.  Now, whenever it is turned on it turns off after exactly one minute.  So, I just can't keep it turned on except by pressing the ON button every minute.  Frustrating!  UPDATE: I was able to repair the control unit.  Fortunately the unit was not glued together but its plastic housing just snaps together.  Inside, the wires going to heating mat were soldered to a small PCB, but one of the connections for the temperature sensor had come undone -- it had been a cold solder joint.  I resoldered it, and reflowed the other connections too because they looked poor.  It now works again.  I'm keeping the one star rating because the unit failed, and most users would not have been able to repair it.
Rating: 1 stars