I've heard great things from them. These really fill a hole in the market. It's either get a bunch of cheaper small power heads and place them all over or spend a grand on 2 MP40s. I was glad to give these things a try. I paid $196 for these 2, $22 for the E300 (I also have the E200 that will go in the sump. I wanted to have this heater in the DT to show the temp, I think the rock cement was $40 and the sump I got from Bob for $40.