Right on. I swear by mine. One difference is that the car will idle at 1500 rpms cold. With the block heater it will rev at 1000 rpm, even after only about an hour of heating. With 2-3 hours of heating in 45-50 degree weather I've gotten as many as 4 bars on the temp gauge straight out of the garage. When I do this, I can go 7 tenths of a mile and be reading 60 mpg on the trip meter. When the engine is cold, I might be seeing 40 mpg at that stage, and the FCD will barely be able to maintain above 50 mgp. With the heater I get full range of the FCD right away. It improves my mileage also, but it's difficult to tell how much with all of the variables involved. This winter I plan to run some tests with and without the heater over time and see if I can quantify the increased mpg.

But the best part is instant heat in the winter time. Especially for my 10 mile city commute!