Here are the Vortex's answers to Leupold MK3 3-18 and MK8 3.5-25. What is the attraction? The MSRPs are 2199 USD and 2499 USD receptively. The punch line is that these scopes, that are built on 34mm tubes with Japanese glass, have most of the high end features, like locking turrets, tactile rotation indicator...etc. The details of these sights are on their websites already, so I will not regurgitate the spec.
And then there is the affordable spitfire line. These 1X and 3X prism sights ( 299 USD and 399 USD) are affordable alternatives to aimpoint and ACOG/Elcan Specter. The 3X model comes with a simple BDC recticle. It is perfect for an affordable AR15 build for shooting out to 300m. The 1X prism sight also has the advantage of working with eyes affected by astigmatism. My only dislike is that the dual circle recticle, I find it dazing and confusing.