The University of Utah's gymnastics program is extremely popular here & consistently sets national attendance records with around 14,000 spectators per meet. Because of that, there are about 8 "pros" that I've seen who are always shooting away. With these 8, it is an even 50-50 split between N & C. I put quotes around pros because I'm really not so sure I'd classify all of them as pros even though their incomes are purely from photography & they have multiple bodies w/lenses draped over their shoulders. One of the people who shoots for the newspaper uses a crop body for everything, and the pictures that get published in the newspaper are simply horrid. This holds true for the majority of events I attend, as I see the same people shooting on the sidelines, be it a cultural event, sporting event, parade or whatever. Having seen the resulting published work in the newspaper & online from half of them, I can honestly say I am not envious one bit. I have yet to run across a pro shooting mirrorless, but I've been told they are out there as well.