I'm in an odd place with Canon high performance (insects and birds for me). For years Canon APS-C was my main camera, with the cheapest full frame for best portraits and night shooting. So rebel xt, T2i, 70D, 80D 90D, then a 6D and later R and R8, both when the sale prices were under 1.1k. During the 80D I got a very inexpensive Olympus EM1m2 for insect macro, stacking/bracketing and the live composite (fireflies mostly). While the 80 and later 90D plus m-pe gave the best single shot macro quality, the set with flash was much heavier than the olympus, and olympus was happier to stack, so 90% of my insect macro were on the Olympus. I started to get into birds, with the same financial and time constraints. I took a lot of shots early in the AM, in low light, and the 100-400 couldn't focus well, especially stopped down with a teleconverter, so I got a 25 year old 500/4IS. The quality and focus were amazing, but I learned I'm not willing to carry that around on longer bird walks, it's really more of a gimbal than a hand-holding lens for me. Around this time the R7 came out, but the combination of loud mirror and rolling shutter (all second hand info from reviews and fora) made me not want to get it, combined with the high prices of RF lenses and weight of the 500. Instead I got the OM-1, traded the 500f4IS for a 300 f4 pro and 1.4 tc, and have a much lighter, sharp though slower, decent focusing system. On the down side, OM system is an interface you have to fight. I have to reprogram buttons and use the custom modes heavily, though pre-capture is fun. I have to use it frequently just to stay in practice and remember how I've set the buttons. In contrast, the R8 is a delight, lighter than the OM-1, I can leave it for a month, set it to AV or FV and everything works, focus is smarter and stickier if not faster. If an R7ii had a quieter mechanical shutter and much less rolling shutter, it would be perfect, but I still wouldn't get around the lens size-cost problem. Probably the 100-500 zoom would be the answer, even slower, but good enough. OM systems makes you work so hard that there is a Concord Fallacy at work to justify sticking with it, and the really good 300 mm lens.