Yes, I tested it quite extensively: Vortex Viper PST 4-16X50 FFP Initial Impressions - Sniper's Hide Forums .
There were some disappointments but the new batch should have those cleaned up. Keep in mind, when you test scopes to that degree you'll find some amount of error to some degree in nearly any scope. That's why I advocate everybody test their scopes no matter what brand name is on the side. Many companies will just tell you it's within spec, but Vortex is going the extra mile.
Still not sold on either. Though from reviews, I don't think vortex is there yet, so I would go with the Huskamaw. My choice still is the VX-3 though. Can't beat Leupolds for reliability and clarity in a lighter weight hunting scope.