I agree. Rads are relatively cheap and last quite along time (years ro decades) but cylinder heads are expensive. The MB coolant is designed to work with aluminum parts, and that's really the protection I want. Ancedotally, the MB stuff might promote longer rad life as we have used it in our 626, and replaced the first plactic rad at 13 years of age and 250K. The Mazda mechanics had never known a plastic rad to last so long. I attributed it to the MB coolant, but more likely it's luck...
1998 C230 "Black Betty"