Digging up an older topic as i am stumped between a Canon 5D mark IV (5DS/5DSR) or a Canon EOS R
Anyone got these and suggestions? I'm upgrading from a Canon 600D so all Canon glass.....I love the look of both but feel the 5D is getting on too much now maybe?
I'd go for Sony A7III or A7rIII and a canon adapter, or if you have the money, a lovely grey market A9. Seriously. They wipe the floor with both of the canons in most departments and the A7III is cheaper.
If you must go Canon, from using both I prefer the 5DIV over the EOS R, and I'm a massive mirrorless advocate. The 5DIV is a mature and refined DSLR whereas the EOS R feels pretty beta.
The EOS R has more or less the same sensor as the MKIV and it was already lagging behind the competition when it was released a few years ago. Compared to Sony and Nikon, the files have limited DR and a lot of noise. AF was slow and finicky compared to the A7III - the EOS R often hunts for faces while the Sony easily tracks eyes. If you're shooting anything fast moving, avoid this camera like the plague. The battery life is pretty poor and it only has one card slot. If you're doing video, it crops 4k (and apparently shutter roll is awful on 4k). The controls aren't as good as either Sony, Nikon or canon (DSLRs) - I found the Fn bar to be pointless if not annoying and the buttons feel cheap. It's got terrible rolling shutter effects in silent mode. On the upside, the colours are nice.
The downside of the 5D is that it's a lot bulkier than the EOS R. It's a proper big brick of a camera - which is fine if you like that sort of thing but I couldn't carry two of them on my 12-hour shoots without having to spend a lot on physio! It's also a lot dearer.
All in all, I've been pretty disappointed by the CaNikon mirrorless offerings. I'd hoped for much more. I'd advise waiting on an EOS-RII before going Canon mirrorless.
If i was you I'd try out your lenses on the EOS-R, 5D and also look at the sony A7III and see what feels right. 600D is a crop sensor camera, so make sure your lenses are full frame, otherwise, you'll get awful vignetting or have to shoot in crop mode. I'm sure you knew that already, though.