Product review (5 stars): Good way to convert a chest freezer to a fridge
I'm not using this for home brewing, but to use a chest freezer as my regular household refrigerator. It's much more energy efficient, partly because the cold air stays in place when you open it, and partly because it's better insulated. Until manufacturers start making home refrigerators in the chest configuration, the best you can do is trick a freezer into operating at higher temperatures. This product does the job. I stuck the outdoor sensor of my digital thermometer inside to check the temperature, and the dial was right on, with maybe three degrees of fluctuation each way.

If you use a chest freezer as your main refrigerator, be sure to get one with lots of baskets! Another issue is condensation. Upright fridges typically catch the water and drop it into an evaporation pan. Freezers don't have this, but they do have a drain hole. I keep the drain hole open all the time and stick a rag where the water comes out, and then use the rag to clean the floor.