A couple of years ago before G-05 was approved for Mercedes use, there was a similar discussion about a Valvoline-Zerex antifreeze that touted by many as being the same or just as good as the Mercedes branded coolant. I called Havoline-Zerex and talked with a chemist there and asked him the question. He said that even though they made both, absolutely there is a difference in the Mercedes coolant and he would use nothing else. Why not call them yourself and see what answer you get? His answer was enough to convince me what to use.

Len