I carried one every day for some twelve years, as a rough estimation. Fine little pistol, although I had several of them as we were issued one pistol once we got deployed and if we were transferred, we were to hand it over at the regional HQ where we were being transferred and they sent the "old" one to our previous station. Some were in better condition than others, but in general is an easy to shoot, reliable pistol. Never had malfunctions using the regular FMJ 115-124 loads. +P were not allowed in this pistol.
This pistol saw service in the Spanish Navy, and was quickly replaced by the much better Star 30M, but its main user was the Guardia Civil (law enforcement) and some units were used (not many) by the "Policía Armada" (we're talking early 70's, Franco was still alive). The "Policía Nacional" was later to be renamed "Cuerpo Nacional de Policía" and to replace their .38 revolvers and BMs by Star 28PK pistols.
The units on display on those pics are definitely ex-Guardia Civil pistols. The Guardia Civil units were traded to Beretta when the BMs and 30Ms were being replaced by the current Beretta 92FS we use. Have a look at the frame and slide, just above the trigger guard, and you'll see the old (the current one is slightly different) Guardia Civil logo.
As some other members pointed out earlier, just be careful if you carry one in the pipe. A lot of these pistols don't have an inertial firing pin and I wouldn't be comfortable with a round chambered and a firing pin so close to the primer. There are no firing safeties, either. The finish could be better, too, but that is an issue that has an easy fix.
Hope you enjoy it.