The Series 80 1911's have firing pin safeties, the Series 70's don't. And I guess the WWI and other repro's are made like the Series 70's.
Ok, the thing about the Glock though is that with a Sig 239, the first double action pull is much harder, but with a Glock the first pull is more like single action. IMO, the Sig would be much safer chambered. I don't mind guns with just decockers as long as they are true Double Action/Single Action models.
For instance, I'm interested in a decocker only Vertec, but from what I understand they only sell those to LEO's. However the safety is nice too, so I might go that route instead.