Getting back to it, assuming the suit could (or could be made to) withstand a moderate degree of punishment from small arms fire, I wonder what the psychological effect would be on your average "insurgent" type, seeing someone straight out of Halo walking towards them, seemingly unfazed by your shots?
In "Fallen Dragon", Peter F Hamilton describes a form of biomechanical body armour he calls "Skin" that makes the wearer virtually involate to all forms of conventional attack, as well as augmenting their strength and endurance. Troy would love it :-D