As long as you understand they aren't target sights I think they work fine. Have a set on my Hi Power. Guy on another site speculates they were designed for guys over 50!
If you want speed and combat accuracy, they work well. If you want to shoot a gnat in the left eye at 15' while it's in flight, then they don't. I have a set on a Glock 19 and they run well during speed drills. You can actually shoot them quite accurately with time and practice.
I put a set on shield and compact, they work well for what they are intended for, but as other have said they are not target sights. Oh yeh kydex holsters still work fine with them.