I think on the Tampa if you attach the yeotek sight it actually gives you a bigger boost in weapons switch speed then the iron sight does and some other random stuff that I've found. I can't remember all of them off the top of my head, but I remember seeing a bunch of other weird stuff like attaching a silencer to a gun then attaching a foregrip to the gun would warrant no stat increases, but decreases only, but if you decide to attach a muzzlebrake instead, it would give it a slight stability boost. ... stuff like that.