Not doubting anything you're saying. But I just want to throw out another alternative.
As stated earlier, I plan on running a 200k BTU DynaGlo Propane heater this winter. Propane is just personal preference for me. I plan on tying it into my main house (500gal) tank that is located just behind my barn. To me, if a person is able to do this, they should. It's a heck of a lot cheaper to run this way after the initial buy-in.
For example, I just had my tank filled for $1.469/gal. 60lb of propane (3 tanks) = 14.1gal x $1.469 = $20.71.
Not to bad IMO for a days worth of heating.
Just food for thought.