YONGNUO YN14EX II Macro Ring Flash for Canon DSLR Cameras, with Adapter Rings and Color Temperature Filters, Hot Shoe Mount, Support M, TTL Flash

I bought this for use with EOS R because I only need a ring flash occasionally and the Canon one is insanely expensive. I found one or two reviews implying it is compatible but others saying it underexposed in automatic/ETTL mode. Unfortunately, my experience was the latter. I tried changing numerous settings in the unit and the camera but could only get acceptable results by manually increasing ISO, which also increases the exposure from background light, defeating the object of using the flash (to highlight the subject only and darken the background). It is useable in manual mode but again that defeats the object of buying a flash with ETTL mode. Note that this unit does NOT have updateable firmware, therefore I would advise caution with newly released camera models. I am guessing a firmware upgrade is necessary for the EOS R and newer models. I returned it for a refund and replaced with Nissin MF18, which works fine with my camera (though nearly twice the price of this one).