My take on all this is...
The Chinese are producing their own designs... well, sort of... and well made US/Euro authentic attys and mods can be found for under $70 and $125 respectively... so it's not that much of an issue anymore. You can spend more, but often that extra cost is in (temporary) exclusivity and frequently - "love 'em or hate 'em - graphics and mostly useless features.
There are only so many basic designs. Most RTAs have some Kayfun influence, and with mechs, there are only so many button designs that have good conductivity... after that, they're tubes and caps - just like all the other tubes and caps.
The difference is often in the quality of metals and of fitments. There's a substantial difference, for example, between the feel and function of a authentic GP Paps button, and a clone Paps. Worth the extra cash? Only you can decide.
When the Chinese stop taking liberties with tolerances... in an effort to increase ease of manufacture and production numbers... their prices will rise and the gap will narrow. At the same time, authentics keep coming down in price and, in some cases, quality. The question is, at what point do they meet in the middle, and it all becomes a wash?