Doug thanks for the link with interesting information. Here is my story. A number of years back I was helping my buddy with a number of other firends, on a special early rifle bull elk hunt on unit 10 for my buddy's 73 year old dad. One late afternoon a number of us were on the top of this hill glassing when we spotted a few elk, which as it turns out were more than 3 miles out. This heard included what we determine to be a shooter bull. We got word to Mark and his dad, and the rest of us were back on the hill watching the stalk, which because of Mark's dad's physical limitations, took the rest of the day.
Well, with good light, the only binos that could confirm that it was a 350+ bull were the 15x56 Swaros. We had a couple of spotting scopes, which also confirm that a shooter was in the heard. The other glass just could not show the definition to get a good sense of the rack at that distance. More importantly as the light dimmed, the other binos lost the ability to see the elk at all, while those who had Swaros were able to watch the entire show.
I am sure there are many makers of good galss, but after that experience I have been sold on Swaros.
By the way, Mark's dad took that bull, which scored 366 with 9 inches broke off the fifth point on the left side!