I would have to agree with you on it being best to have the orifice on the discharge side of the tank.
My great White tank does not have that tiny orifice and I have not noticed any slow fills to the tank. Still it has the slow fill option and fills my tanks and guns slowly. My little Yong Heng probly does not fill fast enough to be able to tell if it slows the fill though. Still it filled the tank for two years without complaint, and my new one does the same, so I see no problem with it.