Personally, I like to put red dot sights on most of my short-range rifles. Iron sights are incredible, but most of the time, it is just so much easier to use an excellent red dot. You get a clear sight picture, and your target acquisition is much better.
Although if you want to shoot medium-range targets, your red dot can start to get a little small. For the optimum close-range setup, you need a 3x red dot magnifier.