I don't dislike 50's, I own several but I do prefer 40's on a hunting rig.
You would need to be shooting at 8x or higher to benefit from the 50mm lens. The human eye can only dilate to 7mm at best, and as you age this decreases. So in a nutshell, anything with an exit pupil of over 6 (obj size in mm / magnification x) is wasted.
Check out episode 9 of the Meateater podcast. His guests are the guys that own or manage Vortex optics. They give a lot of good information on the objective diameters and when you get to the point that you can't get anymore light through a 50mm than you can a 40mm. I can't remember the details but they dumbed it down enough that even I understood what they were saying when I was listening to it.