are you loving crazy
there are some exceptions.
My KS P90 is better than the Echo 1 version.
then again, Echo 1, if I'm not mistaken, cloned KS.
No, stock internals should always be replaced on clones. You can't even compare a stock clone to a G&G, KWA, or equivellent.
Echo 1 rebrands a bunch of different chinese brands, JG, Dboys, Cyma, KS, and Galaxy just to name a few. They give the guns a proper shimjob, make sure it's not a lemon and replace some other internals.