I only suggest that route as a possibility if you plan on doing the install yourself, and that includes any service or warranty work on the item, in you case, a heater.

A local dealer may be a bit more but considering he has overhead costs, that isn't a surprise but that he will be there for you for the install and, if there were a problem, would the internet store be there for free or would the local dealer be there and a whole lot faster?

Otherwise its like bringing your own steak to the Outback Steak House and asking them to serve you it.

Scott