Sorry, I misread a hesitation between a Mamiya / and a Leica comparison. I'm way novice at developing (read: destroying) my negatives... any conclusion one could reach regarding the lens would be more than invalidated by the fact that (pick one or more) my agitation screwed the accutance/my exposure was way under/my development was too long/my dilution too weak etc etc. It would be unfair to Leica.