Rear sight will most likely need shaving to get installed without blemishing (as I did). Front sight requires a drill press to perfectly align, if you don't have one take it to your gunsmith to install it for you.
Pros: Easy to acquire sight picture in very little light.
Cons: Can be difficult to install, suggest allowing gun smith to do it.
This review was written in the old system and had content requirements that are different than reviews written today.