Review on BriskHeat THERMO-CUBE: Efficient Thermostatically Controlled Outlet, Ideal for Temperature Regulation (On at 35°F / Off at 45°F) by Shawn Jimenez

It does what it says it will turn on the power within 1 degree of the set temperature, but it's cheap. This is the second one I've bought and both had grounding issues. Although I gently pulled it out after checking that it was working properly at the correct temperature, the bottom became loose and visibly wobbly. I won't buy it again although I like the idea. It is too expensive for an application. If you plug it in and never unplug it, it might work for you.