Last I paid attention to the value optics, the Vortex Strikefires were supposedly about the best of the imported budget optics. The EoTech clones off Ebay, aside from being trade dress infringement, are said to be all over the place in terms of quality. Many of them seem to have been made up for airsoft guns. Heat and recoil from actual firearms might not be very good for them. I didn't even like my real Eotech, I have issues with astigmatism. Of the non bargain basement optics, C-More railway units are probably about the cheapest thing that I'd want to risk my life on. If the guns aren't for serious use, you can just stick Walmart Red Dot sights on them and use them until they self destruct.