I've read all of MaineSail's stuff on here, and have done a lot of research on the topic. In your case I offer that the alternators you installed weren't necessarily cheap, and not inherently bad for being made in China, but they were improperly specified. One characteristic of alternators is that they are all 150A alternators, it's just a matter of how long they remain alternators.
You can certainly get a high-capacity Chinese alternator that will last a long time. And, you needn't spend $800 on a sufficiently-sized alternator.