Sometimes I just wonder about all of these going mirrorless hype.
For photography mirrorless means for me:
- much better AF: no FF/BF (it was pain in the ass on all my bodies and most of lenses equal to or faster than f/2.8 and I had plenty of them), face/eye-detection, uncomparable more "focus points" -> all in all much faster in use and much more precise AF
- much better auto exposure
- much better DoF control: I can finally
see it in the viewfinder; DSLR's viewfinders are just crap, no matter if APS-C or FF
- histogram, additional other overlays, menu and photo review in viewfinder, no need to often switch between viewfinder and main LCD.
Until switching to mirrorless I took most of my shots in LV, just to overcome the above problems. Now I finally have the LV in viewfinder. No more surprises like "oops, I forgot I am in M and all photos are much-underexposed".
Drawbacks: for me none. Higher current consumption is not noticable for me.
What I consider a hype is fullframe. Especially when shooting FF with f/4 lenses. I see no benefit over APS-C.
Mirrorless APS-C or m4/3 is much smaller & ligher but allows same small depth of field (if desired) and amount of photons per photosite just by taking a faster lens. Taking an even faster lens on FF is not possible or not practicable because a) might not exist (there is e.g. no equivalent of Sigma 18-35 f/1.8 Art) b) DoF will be too small. When shooting f/1.4 with APS-C I consider DoF usually too narrow already. f/1.4 on FF is even worse. I don't see a FF+lens combo, which would give me any benefits over APS-C mirrorless with my Sigma 18-35 f/1.8 Art, Sigma 50 mm f/1.4 Art (+speedbooster being a 32mm f/1.0 lens or 50 mm f/1.4 FF equivalent) + a bunch of other lenses including stabilized 10-xx lenses, pocket-sized stabilized x-200mm, pancake 22mm f/2.0 etc.