Your point is well taken. I thought someone here might know the answer, so I could find out without bothering the folks at Aerial. Since that didn't happen, I e-mailed Aerial and this is what they said;
"There is not currently, nor do we have immediate plans for, a revised version of the Model 9 -- there is no "B" model in the works. The 9 is one of our most recent, and most successful products and it will likely be some years before it is revised."
I have to agree with them. Mine sound great.