I have them on my 40 caliber XDm. When I purchased mine they had a reputation for shedding the light pipes, so I filled the cavities in mine with clear slow setting epoxy. The work great as night sights in the dark and are fantastic in daylight, but at an indoor range that lacks overhead lighting in the booths they are worthless. That's a bit of a disappointement because I do almost all of my shooting at indoor ranges and my eyes are old enough that shooting with post and notch sights is a challenge.

IMO, you have to consider where you'll be using your gun, if it's mostly at indoor ranges fibre optics aren't the answer because constrast sights will be easier to see. If your shooting at outdoor ranges, they are the "bees knees".

PS, as cheap as 4 foot fourescent fixtures are today you'd think that decent booth lighting would be a given. Yeah, I know, some idiot could in theory shoot the overhead, however in all my years of shooting at indoor ranges I've never been in a booth with a bullet hole over my head. Downrange a bit, yeah I've seen that happen, many many times. However I have yet to see one single idiot manage to "miss" by shooting straight up.