They advertise performance on 'premium pumps'. They advertise price on AG pumps. It wouldn't do have data showing that 'premium' pumps didn't have any real performance advantage. I suspect they DO have some advantage, but not that much.

Regardless, you can be SURE the MARKETING department controls what the ENGINEERING department releases!

That said, I'm told many AG pumps are a pain to clean and service, but I'm not sure if that's because of the pump, or the location and piping.