Thankfully, one always has a lifetime warranty on Leupold if/when things do go wrong.
The best warranty and customer service is to engineer it right, build it right, and quality check it before it goes out the door so that it does not have to go back. A lifetime warranty is worthless if you are on the hunt of a lifetime, or the deer of your dreams.
I still have my very first NF, which is the one that bounces between new rifles to check them, has been bounced around for years on more rounds and rifles than I can count, and has been hunting through temps over 100F+ to -25F and everything in between. It was retrofitted with a zero stop and reticle change, other than that, I've never sent a scope back to NF for anything.
Leupold, no comment, other than I've bought my last one. Every time I decide to try them again, I end up kicking myself and end up buying another NF to replace it.
fwiw on usage, My scopes are zeroed for 100 yards, and I dial elevation for almost every shot, so that I can hold dead on, and then I hold for wind and lead as needed.
