Twice in the last few days I have come one link piece away from losing my Zenith El Primero at the bottom of the lake. I noticed that it was hanging on by a single link piece 2 days ago and I just pushed the pin back in and didn't even think to check for the lock ring... Looked down on my return home today and it was in the same condition again. Fixed it correctly this time (with some spare link parts, going to get more on ebay) but that was almost a very expensive vacation. Yet another excuse to start wearing a Suunto Ambit 2 Sapphire as an everyday watch.