Ive never been able to compare them side by side in field conditions. My dad has some vipers but Im not huge fans of them. They're both so different from what Im using now. I also like the vortex warranty so its a tough call for me.
My binocular history last 6-7 years (estimated dates)
1. 1990-2008 Steiner bighorns 9x40. First binos I bought when I was 15. Had them until I was old enough to appreciate and afford better glass.
Looking through them now it's amazing I ever saw anything to shoot.
2. 2008 Burris Signature 8x56- bought on a closeout for $250 or so. Wanted to try newer/better binocs. Liked them, but kept reading about how good Vortex was.
3. 2009 Vortex viper 10x42 - bought them and immediately had buyer remorse. $500 and I wasn't noticing anything better than older pair.
4. 2010 Vortex viper HD - better but still not a wow.
5. 2011 Vortex Razor 10x42 - much better build quality and improved view, but wasn't sure it was 2x better
6. 2012 Swarovski SLC neu - (about time I joined Rokslide) very good but now I had the bug (sold them)
7. 2012 Meopta Meostar HD 10x42
8. Bought cabelas 8x32 (Meostar) for my wife
9. 2013 SLC HD 8x42 sold because felt guilty for spending so much $
10. Late 2013 bought another SLC HD after realizing mistake of selling them. Still have them
11. 2015 bought Leica Trinovid 10x42. Still have them
12. 2016 rebuilt SLC 7x30
13. 2016 Swarovski EL 8x32
Fortunately for used and demos and strong resale I haven't gone broke on the above.
Point of the story - those SLC HD are as good as you will find. You might find a couple of better bargains and save $200-400 (Meostar or Trinovid), but size, weight, ergonomics, image, and resale put the SLC as a tough to beat at that price from Natchez. $1700 retail may be a different story.
Vortex build quality didn't feel the same to me. After a few months of use an emblem sticker fell off. Paint chipped off the body. Warranty doesn't cover the cosmetic. Resale is average and is driven by the warranty.
Swarovski won't cover owner fault, but they do cover a lot and do offer excellent rebuild services for a reasonable price. In my 25 years or so of owning binoculars I haven't damaged binos on my fault.