I bought a Nikon 500 f4G in 2014 IIRC and it has been fantastic for me. It is heavy and I only use it off a tripod or monopod, but it works well when I am am shooting close to the vehicle (elk, swift fox, lekking grouse, etc). That being said, I have loaded it up in the Metcalf and trekked in...
Glacier bears are tame bears.;) This one was on the edge of the Park. I was getting out to take whiz when we made eye contact. I got back in the pickup pronto. She did give me a good shot, but too close for the lens I had. No crop on this one.:D