I don't know a thing about the more expensive Vortex scopes but two buddies of mine bought 3-9 Diamondbacks on sale last year and I've heard no complaints. Between them they killed 7 deer using those scopes last season so apparently they work OK. I myself bought a Vortex Crossfire II crossbow scope last year and so far it's worked great for me. I killed two deer with it last season.
