I hunt blacktail and pig, and have found 3-9X to be adequate. I might go as high as 12X for a long range rifle (500 yds is long range for me), but that is the limit. The reason is glare. In my testing of glare performance, I've found that glare at all magnifications gets worse as the upper mag limit goes up. That is, glare at 10X would be worse for a 6-18X than for a 2.5-10X.
There are lots of good choices in 2.5-10X50 scopes. Just say'in.
