That is a really good question and it depends on what you want. Commercial is different from residential, gas and electric of course don’t have the same criteria and the capacity is really important. We always recommend that you look into the different kinds of hot water heaters and the benefits of things like whether you use power vent or direct vent, liquid propane, natural gas or electric.
Though we service and sell many types of hot water heaters, we personally find that the Bradford White water heater is superior. It is highly efficient, easy to install and maintain, parts are readily accessible, the price is great and it is easy on energy usage. Those are all the criteria we consider when working with our clients.