Potato Jet just posted a super lengthy R5C review. Far from technical but pretty thorough, I learned a few things about the camera like how you can set a button to toggle on/off the EIS. I really like this extensive button customisation, that's a key feature on Canons that I've always valued. His battery test results were also better than I expected even though you'll still clearly need some kind of external solution for a long day shoot.
But now with R5's new firmware fixing the overheat, it has become a much more tempting option. For $1000 cheaper the R5 has IBIS, better battery life, fast photo/video switching, C1/C2 etc.
R5C has all the video assist features and LUT import which is really helpful though. But losing IBIs feels like a giant step backwards, especially considering I mostly shoot EF primes with no IS.
And then there is the C70 with its DGO sensor, ND filters etc. So hard to pick what model to choose from right now.