[Brightcolours]

AF or not AF depends on one's photography. Personally, I never use MF unless I'm doing macro work.

Because it takes time to MF the moment is either gone or blurry. Another issue is that the subject may become impatient, waiting for you to properly MF...

 

I can understand the need for MF when using a SLR/DSLR wide-open since the AF might not be accurate enough or not accurate often enough. With mirrorless, AF accuracy is almost spot on so it's a non issue.

 

For portraits, I actually find the feature detection of MFT absolutely invaluable. It's able to pick the closest eye at a surprising high hit rate. Amazing! Quite a game changer. No more fiddling with focus points or worrying about the subject being outside the array of focus points. I can't imagine going back to a DSLR, let alone MF. We've gone such a long way, it's now so much easier to capture candid moments.

 

It's quite funny to see how much people nit pick about the tiniest IQ difference between lenses when any AF inaccuracy will offset any of the supposedly sharpness advantage of one lens versus another. It's become even more an issue with super high pixel counts. Great, one has 36MP, but in the end 16MP would have done the same job if not better because AF was spot on.

36mp is not that high at all, a 16mp MFT like the EM-1 has a higher pixel pitch so would be equally affected (more so actually, as the pixels get more magnified at equal image size). That the current 36mp cameras appear to have some issues is not related to 36mp (D800 some AF issues and left AF point issues, A7r shutter shake issues). But some Olympus MFT models have shutter/IBIS issues too.

 

I don't seem to have such AF issues as your past DLSRs seem to have been plagued with... My Canon EOS 350D had some AF inconsistencies, but I can't say the same of my 6D.