I used a motorad - made in Israel with a German heat motor. Still OK a year after install. It has a slightly different design than the OEM.
It would be good if someone just sold a replacement heat motor, instead of the whole outlet assembly.
I used AC Delco on my replacement. I still cant understand what GM gains by selling it as an entire assembly rather than selling just the thermostat that sits in the cradle. The aftermarket providers should just sell the thermostat separately is capture the market. I know, too small of a market !