Mercedes Australia conducted a test to show just how big of a difference there is between genuine alloy rims and fake ones. Virtually all common manufacturer rims have some sort of knockoff made that you can buy, but according to this video you really shouldn’t.
I personally have never seen a piece of the rim fly clean off when going over a pothole, but apparently that’s what happens when you don’t have the original one fitted.
Two identical CLA estates are used for the test, one equipped with fakes and one riding the real Mercedes rims.
The pothole they faced did look quite serious, and it had a noticeable edge. That edge is what concentrates the forces acting upon the rim into a very small area, causing the fake to break, while the original shows absolutely no sign of damage.
The original rim could still have been bent out of shape by the impact, but its performance was undeniably better in this particular instance.