I use the Ranger L.E.O. 147 grain SXT and like it. Alot. My R-9 seems to have tamed a bit and likes them now even better than Gold-dots. Usually when a round is labled L.E.O. its in .38 special or 9mm and is usualy a +P+ load. The reason for the L.E.O. spec is because if not in effect, someplace, somewhere, some idiot would load them in a less than worthy pistol with catastrophic results.
Another issue is marketing. Cops are like anyone else, subject to marketing. Back in the day, a "big ole" hog leg was carried as a duty weapon, then along comes Bill Jordan the boarder Patrol/gun guro and he says hey, this things heavy after 8 hours on the hip. Smith & Wesson makes a K-frame .357 to "lighten the load" and so the fad goes towards smaller, lighter guns. Now fast forward to the Semiauto switch craze. All of a sudden departments are switching over to semiautos, most being 9mms. They start carrying "compact versions" to save wieght, with short barrels most of which are not polygonal bored and the 147 grain 9mm bullet is introduced also. So, Short barrel, heavy load, and SLOW velocity. Of course the 9mm benefits from higher velocitys. Stopping powers the pits, so the ammo companys start making +P+ loads to deliever more velocity. They know it will work becuase American 9mm ammos a little weak anyway compared to the original 9mm specs from Germany. Then, the .40 cal is introduced and once again many depts switch over.
