The 5Dmk3 shoots so fast like a machine gun!! (Compared to my 6D) First time ever I'm able to take pictures of my 2 year old running toward me. OMG, I can't imagine shooting with 7dmk2. I always know the 5D would be faster, but this fast? And thank God the grip is bigger. It fits so much better in hand. The buttons and menu! Everything makes sense. (Well, except these rate button and whatever button above it, which are very silly to me). I thought about keeping the 6D for backup but maybe I'll sell it when it's still worth something now. No regrets for having owned the 6D for two years. So many precious moments of my son recorded with the 6D. I know everybody is looking forward to mk4 but mk3 seems pretty sufficient for my purposes.