Re: aim small, miss small
For big game here in the west, I wouldn't use anything over 15x for 2 reasons.
1) A higher power limits the field of view and makes it tougher to spot your shots.
2) In my experience, Mirage gets unmaneagable when the sun is out at higher magnifications.
Just my opinions, I am certain that many very experienced shooters use higher mag than I do.
If some is good and more is better, then too much is just right.
My mind is a raging torrent, flooded with rivulets of thought, cascading into a waterfall of creative alternatives