I've got two, and I have to say they're the best heater's I've ever owned (between my old FW days and my current SW days). They have aluminum heat exchangers so they can't break, and they're plastic coated, so they don't get the oxidization grunge titanium heaters get. They're fully submersible, and their temperature setting is very accurate.
I have a 250W model and a 150W model, and they both get an A+. Probably the ONLY things in any of my aquariums that work exactly as they're supposed to
