I'm looking at getting an ar-15 for all around use, and was thinking either buying an armalite, or a dpms. I've heard that dpms rifles will only except dpms parts, is this true? I dont mind spending the extra many for the armalite if it is better. Secondly what are my options for optics? I want something that is good for long distance shooting and also can be used for fast targeting, my budget is $400 for the optics
