The Honda clone engines are very nice (small engine stuff). Pretty much any Honda OEM part is a direct replacement for the Chinese knockoffs, but usually you don't even need to replace shit. They can do some decent stuff when someone else does the R&D and they attempt to copy every aspect of it.
Sure you can copy every aspect of R&D but the problem comes down to manufacturing. When the original parts were designed to be made at +/-.005" and Fing Fong Wong Manufacturing Camp can only hit +/-.030" then you run into problems. Sure some of the engines may be within tolerance but its really a luck of the draw weather you get a parts thats actually made to the OEM spec. And thats not even considering the material its made out of. All steel is not made the same and they make up their own material certs and say they are equivalent to American specs when they are not.