GUN WORLD magazine used to have a writer named Tom Ferguson who was a retired sergeant at SAPD and was there during their .41 Mag experience. He has been dead for a while. He wrote often about it. From memory, I believe that they only bought one batch of Model 58's. Only a few of the officers liked them, mostly due to the weight of the gun on the hip and the recoil, especially during qualifications, as the alternative to being issued a M-58 was to be issued a .38 Special M&P and, later, a K frame .357. The department qualified with mid-range wadcutter reloads in the .38 and .357 revolvers but there was no reduced loading for the .41's. Thus, it was a far easier task to shoot a high score with the smaller bore guns. Ferguson was a big fan of the gun and cartridge, which, he wrote, put him in the minority.

Whether or not the SAPD's M-58's were delivered all at once or in several shipments, I don't think he ever said.