I personally think that the standard A2 configuration represents the best combat rifle availible.
Its a superior weapon....unless you are in a vehicle, then its too gangly. I do a lot of shooting in a vehicle or in restricted spaces, but appreciate the range and sight radius of the standard A2 so adding a collapsible stock was an appropriate solution. I never have gotten used to the way it looks, and probably never will but its necessity is undeniable. Adding the telescopic stock to a 20 inch weapon makes things much easier in a vehicle or in a CQC scenario. The drawback is that it changes the balance of the weapon and makes it very "nose heavy" and kind of unwieldly, espcially when shooting with the stock collapsed or semi collapsed. My solution as of late has been a carbine, but a tele stock on an A2 is an expedient solution for losing some inches. The range of a 16 compared to a 20 is certainly comparable, but the sight radius is not. The A2 has a definate advantage, especially at long range. At shorter distances, training and experience will negate the advantage of the shorter radius of the carbine or at least equal it. I think the dissapator configuration will be my next AR, as it offers an alternative to the rifle and the carbine by creating a hybrid. If you need to save the length, than a telescopic stock on your rifle is an excellent solution especailly with an issued weapon. In this case, function is way more important than aesthetics.