I'm not sure how I missed this post.
From what I can tell, 'boron board' is a Chinese variation on the traditional cordierite baking stone theme, much like 'schamotte' is a European version. Cordierite, mullite, schamotte, rokite (brand name) and most likely boron board are all pretty much the same thing- kiln fired silica alumina ceramic materials. Within these materials, you're going to have different recipes, some with more alumina, some less, some with other trace elements (such as possibly boron) and different manufacturing processes, so the final products can have different resistances to thermal shock, density, conductivity and heat capacity, which, in turn, produces different baking properties, but... the ranges of properties you see in baking applications are usually not that wide. None of these materials re-invent the wheel.
Ceramic baking stones are almost always going have good resistance to thermal shock and a realm of conductivity between 1 and 6 (steel is 43). While a pizza oven owner is going to have a hard time measuring conductivity (chemical breakdown from the manufacturer really helps), the one attribute that is easy to measure is density. Density tells us a lot. The denser the material, the greater the heat capacity per cubic inch and the greater the conductivity (air increases insulation). Density in baking stones is generally a positive trait.
The 'hollow' descriptor is giving off a corelite vibe:
http://www.mnclay.com/kilns/corelite.htmlCorelite is great for potters that don't want to lug around heavy shelves or for manufacturers that want to save on shipping costs, but it's not so good for pizza ovens. It sounds like they get around the lack of thermal mass caused by a hollow core by having a material with higher conductivity than your average cordierite. The lack of thermal mass is causing the need for recovery time after 3 rounds of pies, but, thanks to the higher conductivity (and relatively high wattage elements), the stones are bouncing back quickly.
Is it safe to say that the hearth pre-heats relatively quickly as well?
I think, for many places in the states, a need for a couple minute rest would be completely unacceptable due to the fact that they have periods of the day with high demand and any kind of down time would leave them in the weeds.
From our other conversations, it sounds like the pace of Chinese pizzerias is a little slower, so a couple minutes isn't the end of the world. Should this recovery schedule ever become an issue, I'm relatively certain that you could do away with it with a solid stone.
Other than the stone, this oven seems to have some very impressive specs. The wattage, for a thousand-ish dollar oven is through the roof and the peak temp is right on the money. Does it have separate controllers for the top and bottom elements? The ad talks about 'temperature independent layers', but, it looks like 'layers' is their word for decks. I see 4 knobs, but sometimes these ovens have one knob as a temperature controller, but the other is a timer. Does this have 4 temperature controllers?
If it does have separate controllers, and is as durable as you're describing, they could sell a load of these to the American market.