Guess I had no idea how common the issues with these rather simple devices. Good to know I'm not alone. Yes, mine fall out just when I"m reaching down to take the shot. Game of chicken?
I too love the Nikon one I have. I bought a long Gepe pro only to discover the gauge of the plunger is thicker than some others (great for big old Ilex 5, but bad for Copal 0 ), I also picked up a used Minette cloth braided release that might be even more smooth than the Nikon. I also have a handful of the "trash" ones just in case.
I like the zeiss type lock, the disc with two positions to catch the cable or let it slide. Fiddling with the screw lock causes shake.
Minolta cables are nice.
I like bare metal best, but they're not too common.
I use a 50 cm cloth one from Schreck most of the time. The length gives it some slack to avoid vibrations. I have a meter long one as well, but it's a bit "sticky" so I don't use it.
I've been through many cable releases, and had many fail. My Fujica G690 needs a good amount of force to trip the shutter, and majority of cable releases fail to do this or only work for a few months at a time.
There is one that I found that's worked and last well beyond all of the others: the Horseman professional cable release. I not sure if you can find them new, but if you come across one that's used, I'd certainly recommend it.