Most of the guys I shoot with have either the vortex fury 5000's or the sigs, and we often trade back and forth when spotting at matches, so I've used both of those fairly extensively. I think most if not all the guys I know agree the glass is better on the sig--I certainly think the sigs have better edge to edge clarity and better color resolution. I dont think anyone has really noticed a meaningful difference in the rangefinders. My fury's I can consistently range terrain out to about 3500yards or a bit more, and game well past 1000, so I have never bumped up agsint any kind of a performance issue with the rangefinder, at least in fairly open terrain--but I've never gotten a 5000yard reading off it either. It aint a vector, but that's not what I was expecting. I haven't used it a ton in really thick stuff to see how it handles that type of "noise" situation compared to other rangefinders. A few people I know have had issues with the RF working in cold weather on the vortex--I'm talking about "we live an hour from canada sub-10-degreesF or less, when out uncovered on a tripod all day" temps, anything warmer than this they are fine. I've never personally had this issue though. I won a vortex 50% off cert at a match and used it to buy the fury's, as I needed a Rf that would work at PRS ranges and didnt really want to spend $1300-$1500. Glass is plenty good-enough for me, but wont impress anyone that is used to top-shelf glass. I havent ever seen any of the others RF binos so cant comment on those.
