There is certainly no harm and a lot of peace of mind in using the factory recommended anti-freeze. In MB's case, it is the MB fluid, in other manufacturer's cases it could be a specific brand and formulation.
It does help to know a bit of the chemistry involved in laymen's terms however.
There are two basic kinds of antifreeze: EG and PG. The EG is toxic; the PG is less so, and advertised as environmentally friendly, and generally won't kill a dog that laps up a puddle of this sweet-smelling and tasting stuff that may appear on a driveway or in a garage. EG is Ethylene Glycol, and PG is propylene glycol.
Both antifreeze formulations are less efficient than plain water at heat transfer. The EG is better than PG. Of course like the good tasting food that is bad for you, the safest and most environmentally friendly antifreeze isn't as good functionally as the bad stuff. In a modern car, however, you'd never know the difference; as long as they engineer enough cooling capacity, you are fine. (Ten years ago, I remember idling in my Ford Explorer, outside temperature was over 100 degrees F; we had the a/c on full blast. We sat idling for an hour and the temp gauge didn't budge off the Normal part of the dial. That's an engineered, modern cooling system!)
In our northern climes, you have to mix the antifreeze with water, generally to what the lowest temp might be. If you live in Duluth, Minnesota you would need a different mix than Washington DC. If concerned with water quality, buy the premix, generally 50/50.
All the formulations contain "inhibitors" which is a fancy name for chemicals designed to protect the metals and seals in the engine and cooling system. I don't know what makes a Mercedes engine much different than any other--you need to protect steel, iron, brass, copper, and aluminum. Like so many other formulated products everyone claims some kind of proprietary edge.
Automotive antifreeze is delivered slightly "basic" (Ph > 7) because as it ages (inhibitors losing effectiveness) it becomes acidic (pH < 7). As Joe notes, that's when the corrosion starts. Follow the recommended replacement cycle and you will not encounter corrosion regardless of what major brand you might use. The antifreeze does not wear out; it is the inhibitors.
I have a heated driveway at home; the system contains 31 gallons of 40% concentration EG "heat transfer fluid". Many systems around here (all car wash properties have heated concrete bays) use automotive antifreeze because it is significantly less costly than "heat transfer fluid". I was tempted to use automotive as well. When I inquired with the manufacturer, Kost USA (who private labels many automotive formulations) I received an education on the topic which I'm sharing here. In my application, you don't EVER replace the fluid, so it is designed for one lifetime fill. Because of that, the inhibitors are in far greater concentration. Aluminum is rarely used in these systems, so there is no protection for that, and the inhibitors are designed for the materials used in boilers. Every 2 years, you drain 4 oz; send it to the manufacturer and they do an analysis and send you back a package of chemical inhibitors designed to bring your old fluid up to new specs. When I owned my car wash, we had a system with about 100 gallons of heat transfer fluid in it. The cost of this stuff is about twice that of automotive.
Regularly changing the coolant, just like your oil and other engine fluids ensures a long life.
