My dope dealer told me in advance that fixes don't last. He said I'd be back. He was right.
All joking aside, OEM parts are not necessarilly the same quality as MB parts stamped with the star on the same product. I have been asking the question of why for 30 years. You can buy a Whaller thermostat for example, and it comes 3 ways. If you buy from a dealer, it will have a star and part # on back and packaged in MB box. If it comes in red and blue Whaller box it will have no inscription on the back or it will have the star and MB part # scratched out with an electric pencil. It may or may not perforn as well as an original. I don't know if the QC inspectors were pulled off the line at the end of the MB run or if the non marked ones didn't meet specs. I don't know the answer, but I've been dealing with it for years.