The $100,000 question! Generally (VERY generally) speaking, the ETA is "usually" the more reliable movement. The best is probably an ETA that arrives assembled to the factory. There are also "loose-pack" ETA's which is basically a bag of parts that somebody has to assemble, so you're kinda at the mercy of the assembler, but the parts are ETA. All bets are off with the Chinese stuff. Manufacturing all the itty-bitty parts, quality control, assembly, etc are ????????? This is not to say that a Chinese movement isn't a very good movement.....I've had them outlast ETA's, it's just kinda up to the quality, assembly, dirt, lube, etc. When you get into modified movements, though.....especially the ones that move sub-dials around, have 100 extra gears, that kind of stuff (ala new "correct" Daytona), I'll pass. Vric's right, though. It's considerably harder to get a Chinese movement fixed than an ETA. Parts simply aren't available for the CN stuff.
Bottom line, you can get good and bad of both. I'd lean ETA if offered, but CN wouldn't be a deal-breaker, most of them are very reliable. Best thing to do is read around a little bit and see if anybody's having trouble with the one you're considering. I guess you pays your money and takes your pick.
