I've been using my 75 1.8 for both personal and work and I never seen an AF lens quite so sharp. I have some top quality Nikkor glass for my FX DSLRs such as the 24-70 AFS and 70-200 VR-II, but the 75 1.8 is in a league of it's own. So does the 4:3 ratio help in creating a more efficient lens? Are M43 lenses easier to design for? Anybody with engineering knowledge regarding the subject willing to explain? I'm just curious from a technical standpoint what makes these lenses so darn good. Any input to quench my curiosity would be appreciated!