The gun is one of the guns that you always see a picture of a Special Forces guy have. While sharing the same great looks with the rest of the Colt series, anyway on with the review.
Features
Its a good size gun to have its not quite an sub machine gun and its not quite an assult rifle which brings me onto my first point which is the three point retractable stock. Which position is best depends alot on the situation you are faced with. While it seems more accurate at long ranges allowing better use of the sights when it is fully extended, but when full in it suits CQB (close quater battle) and being in confined areas like behind a small barricade very well. This is one of the factors that makes me a great fan of retractable stocks, but this comes with its down points, the fact it can't hold a large battery internally but instead houses the small battery. Like i've pointed out in my M4A1 review a small battery is not really the best type at all as the charge can sometimes only last for about three to four games which means fast charging which does not do any battery much good. The EG700 makes the guns performance a very nice balance between range and rate of fire. While the magazine hicapacity size should be than adequate a second one never hurts at all. When you have used 300 rounds and then there is a nice easy kill and you aim pull the trigger and the mag unwinds you feel really silly, oh and out. It is a gun though with quite alot of plastic which while not quite as nice and realistic looking as metal is alot lighter and doesn't rust if you manage to keep your gun that long.
Accessories
There isn't really as much you can easily do with the XM for accessories in comparison to the M4 but there is still big mags, metal body kits, scopes and rails. With modification you can fit an M203 making the gun look even more commando style. I'm not sure about R.I.S. though i don't think it will easily work on the XM.
All in all its a very good gun that performs nicely, probably not your gun if you want to completely cover it in accessories. But a good percentage of people who have owned this gun like it and would probably recommend it highly.