What dfariswheel didn't mention is that the view regarding "necessity" of the Series 80 firing pin safety has shifted. For a long time, whenever the topic arose people (myself included) referred to an article that I think originated on The Sight web site, describing an experiment in which a barrel and slide were loaded up with a primed cartridge and dropped down a length of pipe from various heights onto the muzzle to see if it would fire. The author got to 12 feet with no "Bang," and he quit there because the slide was getting too beat up.
That was then. Fast forward to a year or a year and a half ago and a respected firearms guy, Walt Kuleck (formerly of Fulton Armory) and an associate decided to run the same test ... using a complete pistol rather than just a slide and barrel. They found it WOULD fire when dropped from heights of around three feet (in other words, waist height).
I respect Walt's integrity and motives enough that, as a direct result of his testing, I have pretty much retired any non-Series 80 pistols from my carry rotation. I mostly alternate between a Colt M1991A1 and a couple of Paras ... all of which have the firing pin safety.