To comment on the shooting tangos after they are surrendering and lying down; I didn't see the program you are talking about and I am not an expert on SAS engagement, but to support their tactics it may have been possible that intel predicted remote detonating explosives in the area or something to that effect.
My choice for CQB and urban ops is my Bushmaster A-3 shorty equiped with a Trijicon ReflexII, Surefire M500A tac light, high cap mags with Winchester silver tips, one mag of green tips for penetration, Giles sling and an ACOG 4x in a pouch incase it's needed. Riding second seat would be my Glock 17 with Trijicon night sights, ITI M-3 tac light, 5 or so extra mags loaded with Pro Load 124gr. Gold Dots, in my Safariland 6004 tactical rig. Don't forget the class III ballistic vest (in case someone is a little faster).