“This is just as good as the performance parts made by the more famous brands, except ours is much cheaper…”
“Don’t worry, these performance parts are produced in (insert name of Asian country other than Japan), but they are just as good as the ones from (insert name of European country)…”
These statements, or something along the same lines, should be familiar to anyone who has ever walked into any shop selling aftermarket products and services for cars.
But these claims usually cannot be proven. Even if a petrolhead tries his best to verify them with his “butt dyno” or laborious real-world testing/recording, they can be subjective.
On a more rudimentary level, we cannot even be sure the products in question are safe for use! 
