Re: IOR Binocs?
It depends on where you will be glassing. If you will be in wooded areas where you will not be able to see more than a few hundred yards, then the 8x would be better, if it is wide open country, then the 10x would be better. I personally use 12x50 binocs for the open spaces here in southern Idaho for looking for deer, rock chucks, coyotes, etc. In many places here, I can look miles away for animals.
I'm sure someone will chime in on the military rangefinder reticle - I have no clue on that.
I keep nature balanced - I hunt everything!