I have a laars lx-400 ng heater. It is very good at raising the temperature quickly, and seems to be efficient. Unfortunately, after three years of service, I had to replace the electronic control panel to the tune of 580$!!! That is about a third of the total cost of a new heater, which I think is ridiculous. Perhaps there are better models out there. I almost bought a whole new heater just to have spare parts for further down the road!

EricF