Hi, I have Bronica SQ-Ai with a lot of lenses etc. Some of they are older S type lenses. The 3.5/150mm and 2x tele converter. The common 'internet fact' is that PS serie gives much better contrast and is not as flare prone as S serie. But has anyone really done documented comparisons? Would I gain any visible difference by upgrading 150mm S lens and 2x S tele converter to PS serie?