first is the price.price different is high.for ori at least 7k above(once i check the 17inch 9j spec rm7.5k for used one,new is difficult to get).those immitation in market around rm1.5k++
second is the quality.quality is for ori rim of course better.those rays are forged rim.so it is obvious stronger.but they even can break.i visited the half cut place,i saw broken ori rims including rays.maybe they use it for racing purpose..car went into collision.im not sure.so for immitation u can imagine the quality yourself.by the way,for daily use i don't think it is pretty bad.most of my car club friend use immitation.no big issue for fast driving/forced handling etc
just my opinion.

lol