"...Seems that the hinge type are far superiour, but you don't see too many cops carrying them..."

Many officers only have what is issued to them, they won't go buy any equipment on their own. I was just the opposite, I spent a fortune over the years on what I hoped to be better stuff. One bad thing about the hinged cuffs is that you can not use them with many of the handcuffing techniques departments use. With my former department, I was required to use their approved techniqes ONLY, if I tried something different on my own and got hurt in the process, it was a "preventable injury." But ya gotta do what ya gotta do, so I carried both typed of cuffs (two cases on my belt), and had about six or seven more pair in my bag...