I'm not a huge fan of fiber optic units on duty/carry guns.
For serious use I'd get some Trijicon HD sights or some steel night sights.
The XS line is good too.
Fiber optics may crack or break in a real critical incident.
Trijicon is in use with many military & LE agencies worldwide.
See www.Brownells.com www.trijicon.com www.natchezss.com www.midwayusa.com www.policehq.com