I think you should contact them, I heard they sold quite a few ovens in the area. If you are in Rockville, you should go to the Bolger Center in Potomac, they bought 2 of the Bread Stone Ovens ovens made by FGM, for their bar the Pony Express Bat and Grill I think is the name. They do live pizza cooking every Tuesday and Thursday night, weather permitting. A friend took me there and it was the best pizza ever and the ovens looked really good.
Also I went to the Bread Stone website and they are located in Laurel, I am going to call them to see if I can look at their ovens and talk to someone.
I will keep you posted of my findings

Thanks for all the comments. Yes my main concern was the height of the dome, as I think I can partially wall off the entrance to keep heat in. Perhaps I can redesign it with a lower roof.
It is too bad it is a new company as there is no feedback from people who have built it... Do I feel like being a guinea pig?
BTW I am in Rockville.