I recently purchased a standard USP .45F with factory installed night sights. Does anyone know what kind of night sights they are? Also, are they fairly comparable with aftermarket night sights? Someone told me that getting factory installed night sights are like buying a car with factory upgraded wheels...that they are inferior to aftermarket ones. That kind of made me mad, because as a novice in handguns I figured I would be better off letting Heckler & Koch install the night sights with the ones they figured would work well with the USP. Any thoughts?