What is interesting is that Agressor has self-admitted that they are comparing apples to oranges. When claiming that their "A" impeller has the same design characteristics as a Berkeley "AA" impeller, they admit that they are dissimilar impellers. "As you can see, it has an open face..." or something to that effect. "Water travels longer..."
With similar performance characteristics of a Berkeley AA, it sounds like they need to put the Aggressor into a different box, labeled "AA". You will see big mph gains going to a Berk "AA" from an "A" if you have the motor for it.
If you are comparing two similar impellers, and one has a performance increase because of weight, cup shape or something like that, then yes... You are comparing like products. This is like Merlin calling a 509 a small block, because it is less cubic inches than the 540. That doesn't mean they can compare it to a 350 Chev!
Aggressor, re-name your "A" a "AA", and then compare it to a set-up Berk. Apples for apples guys...