Presumably this is an "honest" mistake via incompetence by the vendor, with horrible follow-up to remedy said mistake. The same of course happens with every vendor located anywhere in the world. It's getting much worse lately in the US as far as I can tell.
The difference though is your vendor using a lower grade metal than specified, knowingly and with intent to defraud since they decided that you might not notice and/or care enough for it to matter. That sort of thing doesn't seem to happen as much in the West.
I do agree that the reliable Chinese vendors will make things right at their expense if you can prove that they did not meet what they agreed upon. This is basically how I choose to deal with a vendor or not in China (or anywhere, for that matter) - I know stuff will happen, but how hard did I have to fight for them to make it right?
The difference though is your vendor using a lower grade metal than specified, knowingly and with intent to defraud since they decided that you might not notice and/or care enough for it to matter. That sort of thing doesn't seem to happen as much in the West.
I do agree that the reliable Chinese vendors will make things right at their expense if you can prove that they did not meet what they agreed upon. This is basically how I choose to deal with a vendor or not in China (or anywhere, for that matter) - I know stuff will happen, but how hard did I have to fight for them to make it right?