This is from a dealers perspective on the companies we deal with.
As some have stated, Leica terrible on warranty to deal with, usually 60 days or more if they will even take it back.
Zeiss is not as bad, usually 60-80 days as most they send back to Germany for repair.
Leupold I have a good relation with and usually repairs done in under 20 days or item is just replaced.
Swarovski is easy for repair and or replacement. I have a good rep that handles it. Usually within 15 days I can have it repaired of if it's an emergency within 3-5 days.
Vortex is the easiest I would say on warranty. I have a great rep. If it's an item we have sold and you bring it in to us and I have another one the shelf, I just replace it right then. If not, I call rep and new one arrives within 3-5 days and it is replaced. They pay all shipping and replacements.
We sell over 300 Vortex a year,mostly the Crossfire series with very few ever returned for warranty.
Leupold in the 200 plus a year.
Swarovski is around 250-300 a year.
This is from my perspective as a dealer. Hope it helps some of you.
Mark