If we are talking competition as opposed to self defense, don't bother with a Tritium-FiberOptic-type of night sight. You are paying for a feature you don't need for shooting in the daylight.
I went with a Truglo TFO on the FS M&P 40 slide, as this is how I normally leave the gun set up for home defense, where there is a potential need for shooting in the dark. Also remember that the tritium light source WILL fade eventually.
I use the 9mm slide for occasional competition shooting and range practice, always on a lighted range or outdoors during the daytime. For this kind of shooting I like the Williams Fire Sights. They are very bright, even in dim light conditions.
Better yet, the Fire Sights also come in an adjustable model, which is more critical for my FS M&P 9 as the point of impact is highly dependent on the type of ammunition and range. They are also CONSIDERABLY brighter than the Truglo TFOs in the daylight.
As for installation, I bought a sight-pusher. Strictly speaking, you don't need one for the Fire Sights, but I did need it for the TFOs. I went with this product:
Fisher Solutions - Handgun SIght Tool - El Cajon, CA