I ran Continentals 30 years ago when I lived in Germany and they were great.
A few years ago, I put a set on my '96 E300D because they were much less expensive than Michelins and they were again great.
In sharing posts with another fellow who bought a new C240 at the same time I did, he said that he had Continentals and they were very noisy. I did not have that problem.
They seem like a lot of tire for the money. When I bought them a few years ago, I mail ordered them and it seemed that Continental was making a push into the North American market. I don't know if they were selling them cheap to get some market penetration or they were just cheaper made tires, but I was happy with them.
You can go to the featured cars forum and find the C240 posts to read about his bad experience. He is so dissatisfied, he posted a remark that he is going to scrap them and put on a new set of tires. That's pretty dissatisfied.
Driving as many miles as I do, I go through alot of tires. I've probably driven close to a million miles total on Michelins and have never had anything to complain about. They are round and always balance out well and last a good while. My experience has been that even though they are expensive, you probably spend less money per mile, just because they last a long time and if they require rebalancing, it's because you lost a weight or something.
Good luck with your decision.
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in