They are good enough for Zeiss to have them make their scopes! I have a Optika5 in 4-20x50 as well as an Optika6 1.5-6x, both with my favorite hunting reticle, the BDC-3 Illuminated reticle. It is my favorite reticle, even in the standard BDC without Illumination. very very clean MOA reticle. The illumination version is one of the best for shooting in the dark, even twilight it does go dim enough, most don't.
The adjustments are spot on with either scope, and tracking is spot on. If you want to dial, have it 11 moa will be 11 moa, and back to zero will be right where you left it. As for the glass, well everyone comments on how good the Zeiss glass is, they understand, it's from Meopta, and this shows with Meopta scopes. I replaced the 4-20x50 Optica5 with a new 3-18x44i Leica because I wanted the shorter length and more clearance for lower mounting on a sporting rifle. Even thought the Leica had a 30mm tube and the Optika5 has a 1", it's very hard to see a difference in glass, That's saying a lot, as everyone who has ever had a Leica optic knows, they are great!
I've owned Kahles S&B, Zeiss, NF, Leica, and can assure you, Meopta deserves to be listed along with these scopes, in a league of their own above all others. Durability, function, and optics, and for me the BDC reticle is one of the best. I will be buying and using more!