I’ll make this post short. I bought a Vortex Defender MRDS to replace a Romeo0 on my backup P365X carry gun. It came, I took it out of the package, and put in a battery to function-test it before I did anything permanent.
It has a TERRIBLE refresh rate at anything other than max brightness. Like, I could cant the optic up and down at a very moderate rate and see a trail of red dots with substantial gaps between them. I have literally never seen this problem before, including on some really cheap optics. I am not sure what caused Vortex to make this design decision, but it was a terrible idea. Unfortunately, higher brightness levels caused substantial halo with the red dot as well. (On the plus side, it got very bright.)
I returned it. The 507K is still the RMSc footprint optic to beat. I thought everything else about the Defender seemed pretty solid, but those were deal killers for me. Keep in mind that this is coming from a guy running two UH1s, two Razor LPVOs, and two Razor RDSs. I am perfectly happy buying Vortex. But the Defender… not so much.