I can not resolve any more detail with my 65 swaro spotter than I can with my Slc 15's, you might be able to get more magnification but that doesn't mean I can resolve more detail. Unless I was an antler point weenie, I would take the Slc's anyday if I had to choose one. Much easier to 'glass' with. All the Elk I have found have been with my 15's. An 85 or larger scope would probably be a different story.
I did take the below pic with a spotter, (last day, before we flew out.) but I found him with the 15's from somewhere between 1.5-3 miles.
In the pic with the Slc's I found Elk at around 6 miles on the second furthest peak you can see, I could tell if they were Cow or Bull. Pic was again through the scope, all freehand.