my experiences & observations..... I'm no expert, but I know what my eyes see. And they aint as good as they were 20 yrs ago - so may be a good test for scope optics quality. I am also not wedded to any one brand - so my views (excuse the pun) are non biased.
Have or have owned a bunch of scopes including pretty much all the ones referenced above - swaro, Zeiss HD5 & Diavari, Leupies (VX3's and VX6's), Nikon, NightForce, Trijicon, Kahles, Burris and .... and Vortex. The Euro glass is definitely a step above /beyond the others & you'd expect that for $$ paid, VX6's are close but not quite as bright/clear as Euros.
My observation of 4 different Vortex's (all Viper PST's - two 4-16x50 & one 4-16x44 & one 2.5-10x44) is that quality is variable. The first 3 were very good optical clarity & resolution. Side by side against NightForce both set to 15x the Vortex's were noticeably better & greater clarity. And significantly better that VX3 or Nikon. Sadly the 2.5-10x44 PST is not a shade on the optical quality of the others. The 4-16x44 (my sons) has been back to get fixed after it lost zero after a bumpy ride up some hills. Replaced/fix no questions asked and now works fine but should not happen in the first place.
I think this is the biggest weakness for Vortex - they are variable in quality - thus why you see such varied comments - people love 'em or hate 'em depending on what the bought. You can get a good one or a bad one, although the "bad" rate seems to be not too high.
If Vortex would spend a bit more time & $$ in fixing their base quality then they'd be onto a real winner.
By no means is Vortex the only scope manufacturer to have quality variation or issues.
The Zeiss HD5 - I have one that is super good/clear optics (3-15x42 w Z600 reticle) .... it was sooo good I bought a 2nd one, also 3-15x42 but plex reticle with dial up turrets. The optical quality on this one is NOT as good as the first. Not as sharp/clear. Good yes, but noticeably different.
Some reports of issues with early VX6's as well, but they seem to have that sorted now.
I would not bag Vortex's ... they are good value for money, have great features if you like twiddling with turrets ....just be aware that the quality/reliability does vary. Make sure you look thru the scope before you purchase it and get it back to store if you have any issues. If you get a good one, they are very good. Just don't expect it to match the euro glass or reliability.
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