I think Trijicon offers the best night sights for S&W 3rd Gens, as they have a variety of sights specifically made for the different 3rd Gen models. Accuracy is good, fit is excellent, and they also offer to re-lamp their sights when the glow runs out.
I also like the XS Sight Systems 24/7 night sights which are 'dot the I' style sights. These offer a good sight picture for fast, simple target acquisition, and are accurate enough for defensive shooting purposes. They offer different models for different 3rd Gens as well, but I have found that the fit in the slide dovetail is a bit looser than Trijicons. With these sights, it is recommended by XS to tap the sights in, and not to use a sight pusher with them.
If you do decide to install your own sights, there's always the chance that something will go wrong, and it may wind up costing you the sight (or damaging your gun). For this reason many people find that it's just easier to have a professional do it instead, especially if it's only 1 or 2 sights that they need installed. I've wasted 2 front sights and one of EPJ's sight pusher's learning to do this myself.
Personally, I tap in all of my sights these days with a plastic/wooden/brass dowel, often using a 50 oz deadblow hammer (gently). The main danger with this method is that you may hit the sight so hard that the Tritium vial gets damaged, so start gently and work up from there (though Trijicons are pretty tough IME) . On some sight models, it's also easy to slip and knock the front sight post off the base.