I have the Viper Micro Tune on my hunting bow and the Copper John Dead Nuts 2 comp on my 3d bow. Both are top of the line great sights. Overall for durability and the ability to microadjust even the pins the Copper John has the edge. The Viper sights do not have microadjust pins and I have broken 2 fibers this year on my hunting bow. With that said, I have also dropped my hunting bow out of the case, onto the driveway, directly on the Viper sight and it didn't budge one bit. I like that the Viper sights are camo (stupid I know).

Either sight you can't really go wrong, but for pure performance, the Copper John has a slight edge IMO.