I have a swaro 20-60x65 spotter and rarely do I ever zoom much further than 35ish. If I had to do it over again I would get the wide angle zoom 25-50 I think it is. I am usually glassing in the 400-800 yard range.
I started with a 20x60 eyepiece on My Swarovski , then bought the 25x50 Wide angle. Glad I did . The 25 stays on the scope 95% of the time