You might consider getting your oil tested after using the MB oil & then the Hyundai oil. Check out BobIsTheOilGuy.com. Do a search on the BITOG website for oil test & it will give all the info. Costs like $25 or $35. Anything other than a test of how your car reacts to either is only conjecture. Hyundai makes some good cars & their engineers aren't going to screw them with bad synthetic oil, but do the test to prove it. My 2 cents.