Take a look at TruGlo TFOs.
Fiber optic rods that use ambient light to brighten a three-dot sight picture, with tritium embedded in the mount to provide night sight capability.
I have them on my EDC XD-40, and am very pleased with their performance.
According to TruGlo, the problems of breakage alluded to in the following video have been addressed.
[ame]http://www.youtube.com/watch?v=xhZ4GKik5Qo[/ame]
I have both Trijicon and Meprolight night sights on other pistols and don't see much of a difference between them.