Works great. Allows one partner to use the heating element to stay warm both in winter and summer and allows the other partner to not use it and sleep comfortably.  Should have bought it sooner to stop the nightly "its too cold" or "its to hot" debate.

Pros: Good value. Easy to use.
Cons: The receptacle for the plug on the foot of the mattress is bulky and placed right where I put my feet. Feels uncomfortable.