I've had a Monarch 2-8 for several years and recently purchased the Viper in 2-7. I'd rate the Nixon higher than the Viper in clarity around the edges, but other than that haven't used the Viper enough to say any more. Both are plenty sharp at the center where it matters.
My eyes find the clarity thing swapped, but like JGray says, they're pretty comparable. I compared the standard "plex" reticles in each, & my eyes preferred the Vortex.
We're all different, but you're not likely to be displeased with either scope.
FC
