Canon R5 or R5C?

Regarding the two disadvantages of the R5c relative to the R5, I can comment on the actual real world differences (and provide examples above) since I actually own and have used both cameras.

IBIS- Although the R5c does not have IBIS, the overwhelming level of stabilization with OIS equipped lenses comes from the OIS. Using exactly the same RF24-240 & RF100-400 on both cameras, I have found the difference in the stability to be of no great significance.

But what about non-OIS lenses? My only non-OIS lens is the RF50mm. By switching on even the lower level of the two available electronic IS settings, the stabilization is very good. The only price you pay is a slight degree of crop. In situations like this internal IBIS would be preferable if you wish to avoid any crop, but the results are still very good.

AF- The biggest difference I have found is the absence of animal AF. However in day to day usage I have not found significant differences in the overall AF performance.

The video above was shot all handheld, with the R5c, using the RF100-400. AF was used exclusively. Many shots were close to or at 400mm. This is not only a significant test of the AF with animal subjects, but also of the real world stabilization when using OIS lenses. I would be happy to provide examples of the non-OIS 50mm lens coupled with the electronic stabilization of the R5c. Again, IBIS would be preferable, but the degree of difference is simply not the great with OIS equipped lenses. The electronic IS is there for non-OIS lenses if needed.