Firearm enthusiasts don't agree on a lot, but one thing that's universal is that factory Glock sights are ripe for upgrading. The plastic, three-white-dot arrangement doesn't give much contrast for rapid shooting and is difficult to use in low- or no-light situations.
Meprolight offers a number of tritium night sight upgrades for Glock handguns, the most recent of which is the R4E Duty Sight. Rather than a three-dot arrangement where all three have tritium tubes, the R4E offers a front tritium dot and three reticle-like marks on the rear sight.
The R4E sights feature aluminum construction and install like the standard sight upgrades. The R4E duty sights are currently only available for Glock handguns, but are expected to expand the line in the future.