It's larger and heavier than the German MG151, in its original 15mm caliber,
ballistic performance is similar to the MG151/15, but a much lower rate of fire,
420rpm vs. 740 fir the MG151. The RLM felt the 15mm was below performance
requirements so the gun was redesigned into the MG151/20, dunno if that would
happen with the 15mm BESA as the Hispano was already to hand.