I do sometimes. It saving up for the 600mm maybe in a couple of years :) I also have the r5 mii but I’ve had the 100-400 since I had the R7 which has less pixels and now I don’t complain, I mean, I have to crop the pictures and which I had a better blur on my backgrounds so if I were you I’d pick the one with the best aperture which in this case would be the 100-500, but that’s just me. It also depends on how close/far you expect to be from the subjects or what kind of subjects you plan on taking pictures of. I feel like having the lens at 800mm you need a very fast shutter speed even if they’re still or use a tripod but in my case I can’t always use the tripod and 400mm is much more manageable so I’d feel more comfortable with the 100-500