There are several subjects that have been debated nearly to death on this forum, and yes, as you have already been warned, oil and antifreeze are the two hottest topics. And, yes I said antifreeze. Coolant is a misnomer. Antifreeze isn't a cooling agent, water is. That's why you mix the two. Water to cool the engine, antifreeze to keep the water from freezing, and from causing corrosion.
I will be the one this time to predict "flaming folders" for this thread. Whenever you see someone bring up either of these subjects in the future, respond as you would in a battle zone when you hear the cry, "INCOMING!".
Here's my, IMHO, thoroughly researched synopsis of your questions. First, Green antifreeze ist nicht gut. All Green ethylene glycol based product contains phosphate corrosion inhibitors that can hurt your engine and cooling system. Stick with the Mercedes stuff that uses an ethylene Glycol base with a corrosion inhibitor called "Glysantin".
The two most helpful/damaging components of antifreeze are the additives, mainly corrosion inhibitors, and silicates. The wrong mix of either/both can hurt your engine, cooling system, water pump, and mainly your wallet. Use the stuff that was made for your car.
Second, Mercedes now ships all of their cars from the factory pre-filled with Mobil 1 synthetic engine oil. (My mentioning this has now set off red flags, and the Dino/Mineral oil users out there, and you know who you are, will be posting to rebutt.) Here's a recent discussion about synthetic oil:
Getting Rid of Synthetic Oil
If you are a wise person, you will follow the lead of the company that made your car, use what they use, and change it when they say you should, or sooner.
If you are one of us nosy, gotta know why, let's review the materials one more time, what's the data? kind of guys, then you can do a search in the archives, use the links kindly provided by yal (thank you, yal), and check out all of the links posted in those threads that go to the websites for Mobil, Castrol, Valvoline, RedLine, Havoline, Peak, Sierra, and a host of others.
Here's some related topics that are also highly subjective:
1. Change oil by draining, or vacuum pumping?
2. Use distilled (or demineralized) water in your cooling system instead of tap water?
Don't worry, it's all covered in the links to previous discussion threads...