It sort of depends Tony. Consider if excess microwave concentration is directed into an area of the chamber that has poor water circulation, resulting in excess heating of the water in that volume, leading to vaporization, yielding a blown out unit (which is sort of what may have caused the last 4 or more month delay).
If the valve is on the water source side, which it should be, then opening the valve should cause a pressure rise, marginal but not a drop. So their test did actually test something. The fittings fit this time. Hey, don't laugh, that apparently was not the case for the meet and greet.
Now let's see that they do not blow it up. Then those as soon as possible in-house numbers Robert once mentioned, even if only amateurish and subject to correction when the professional numbers are released in short order.
Basically, I am not satisfied with a barbecue until I see how well it cooks the meal.
PS
Was anyone surprised that the company that makes the water-cooled magnetrons would be willing to sell them ? Why was that mentioned like it is some sort of major milestone ?