I cannot speak on the Vortex offering, but I do own a Sightron S3 6-24x50 LRMOA and in my opinion it is fantastic. Glass is amazing, turrets are great with positive audible adjustments, and adjustments are repeatable. I am definitely a fan of the Sightron scopes (I own four of them) and warranty issues do not concern me as I've never had to use the warranty and if I did, either Hirsch Precision or Mystic Precision will look after me properly; I am certain of that.
I'm not saying Vortex is crap, but with more and more shooters on here moving away from them due to warranty issues and increasing costs, I would be hesitant in the very least.
My two cents...