Glock
I guess I'm the only person on earth that LIKES standard Glock sights. I think them among the best out there. I've owned many Glock's, still own 3, never a problem of any kind. And I can see them with my old eyes. I read people complain as they are plastic. However, I've never known anyone to actually have any problems at all.
Same with the "plastic" guide guide rod. I have well over 10K rounds through my 3 keeper Glocks and never a problem. Never seen a problem with them (I have seen a problem w/after market steel ones!!). I've watched a video of a Glock fired until it catches fire and the guide rod is flaming, melts and falls out, and the Glock is not hindered at all and keeps firing. In my opinion, if anything is on a Glock it's pretty well engineered, thought out, and will work. A "up graded" or "dicked with" Glock is USUALLY a "lesser" Glock. I avoid them like the plague after having several. I've had Glocks with professionally "slenderized" stippled grips, extended mag release, extended slide release, etc.etc. I never felt any of it an improvement. Just my experience and opinion. Your mileage may vary.