I don't shoot m4/3 because of size

Some have a need to believe what they shoot is the end all/be and their equipment must be the best.  Personally, I don't care if my camera is #1 or #100 - does it get the job done for me is the better question.

When I switched to m43 earlier this year, IQ was better than I was getting with my 4+ year old DSLR....but better than a brand new state of the art DSLR - well doubtful.  Rather likely close enough to where I wouldn't notice in most situations is likely a better answer.  The new top DSLRs still have better DR and low light performance, also better continuous focus.

However the size and IQ together trump any advantage of a larger format system --- for me.

I dont shoot video, so don't care about any advantage there, but mirrorless in general will have an advantage over the traditional SLR.