Guess I'm guilty - we run our heat pumps whenever possible because:
A - I don't pay for the electricity based on consumption
B - The heat pumps on this unit are super quiet
I had the cheapheat idea in concept several years ago, and got talked out of it by a supposed expert that said it couldn't be done. That could be my patent now - power to the guy, he stepped where I wouldn't, and they look like nice retrofits. The only flaw I see is the output does not match the burner (that's why he slows down the fan), so although it heats the pipes underneath, I don't think it could keep up well enough in the temperatures that would actually threaten the pipes. I may be wrong, but just a hunch.