Something I have noticed before with the Westpac 412 SP at Newcastle they are about the only 412 operator in Australia operating with their Nitesun in the forward position just under the Radar ,all the other operators have moved their Nitesuns back to just fwd of the fwd crosstube , in the Fwd position as on the Newcastle machine then the aircraft is limited to a max speed of 100kts (as per flight manual sup) , how often has that machine been flown over 100kts with the Nitesun fitted? (which is why all the other operators moved it back , as in the aft position no speed restriction applies!)
But obviously their Engineering and Operations department know this and Placarded the instument panel with a decal ( Max Speed 100 Kts with Nitesun fitted)and enforce the speed restriction......