I've been very happy with the Auber controller:
http://www.auberins.com/index.php?main_page=product_info&cPath=8&products_id=334
More expensive than a STC-1000 set up, but it's all pre-wired for you and ready to go (and it displays ºF). I use one for my chest freezer and another for...
I use a similar setup indoors with good results (on a smaller scale). In my rig with a single small heater, an aquarium pump is pretty important in getting an even temperature around the whole water bath. You don't need a lot of water movement, just a little circulation to increase convection...