RIMZ, and without any question. I have an older (un-fluted cylinder) Smith 610-3 and have fired thousands of 10mm and .40 S&W rounds (of all types) from it; it is a truly wonderful N Frame.
RIMZs are SUPERB moonclips. They cannot rust, they do not crimp or remain bent/distorted out-of-ideal shape, tools for installation and/or removal of cartridge cases are not required. and they are extremely durable; I have never worn one out after literally thousands of rounds fired. This is all due to their precise polymer construction. I have used them for competition, concealed carry, pest hunting, target shooting, plinking, and self-defense (both concealed carry and home protection). In every instances, their performance has simply been flawless; I cannot recommend them too highly.
I would NEVER consider traditional, steel moonclips after many years for experiences with RIMZs.