All these clones are pretty crap, however they can be made acceptable for air gunning with a little modification.
This is the difference really, if you want something that just works and will continue working then the original is the only way to go!
If you live in a country that charges exorbitant customs and taxes then the original may be out of reach (read double in price) so the clone presents a value proposition that is difficult to ignore, 10 clones or one original...
As stated, locktite, a correctly sized washer some lube in the right place or some rubber feet glued onto the legs and the patience to fix something that should just work is what’s needed.
Counterfeit goods are deplorable, sometimes what I deem counterfeit is actually made under license, I work for a large US manufacturer of computers, what we do to hide the manufacturing location of products is actually quite funny, but a little google foo quickly reveals the truth.
I cannot talk to the Accu-Tac clone, however I have found that at least some of the better Atlas clones are made under licence for the air soft market, while some are clearly scrap metal. They all need work to function correctly.
How to save yourself? Buy legit and rest easy or accept that your going to have to do some homework to make a product viable.
Unfortunately there seems to be no right and wrong when profit (manufacturers) or saving (consumers) is the motive.