I suppose the responsible thing to do would be just buy a used/low-shutter count 5D III to hold you over till the upgrade comes, because the 5D IV/5DX - whatever it's called - is probably your camera. But, if you're not necessarily a high volume shooter (event/sports/wildlife shooters that take huge numbers of shots) then you might give the 5DS/R a try. I do love mine and Canon made it specifically for studio, architecture, and landscape shooters, but I know you're concerned about the huge files.
Yeah, I've really come to like having the option for high resolution. I'm thinking of getting a 5DS and then maybe a 5D4 or even something like an 80D for events and high volume shoots.
Anyway, I guess this really isn't a topic for this thread anymore. I'm kind of bummed because there was a lot I loved about the Sony A7 bodies.











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