We have had one for the past couple of years. My wife drives it. Luckily, the previous owner was great about maintenance and kept every receipt. The car has been great. Changed the plugs and wires, air filter, oil changes etc. The window regulators are an issue. So far, we have replaced two. The PO changed some too. Not a difficult thing to do but an annoyance. The mass air flow sensors on this era Mercedes are always an issue. They can be cleaned with CRC mass air flow sensor cleaner. Eventually they need to be replaced. Just the way it is. I have not have to do anything to the MAF yet.
Also had to change the door switches. The alarm kept sounding. Easy fix. Took a few minutes. Rear brakes...straightforward.
I am sure you know the w210 E55 AMG is not supercharged like the w211. It still is surprisingly fast.
Here is a picture. The "sports grill" was replaced with the original.
