1) Do never use K&N air filters in a modern engine (with MAF) because the oil emanating from it will kill the MAF. Use only OEM air filters.
2) Japanese are 10x better than Germans in designing electronics stuff. Have you ever seen Germany-made computers or consumer electronics in the US? Lots of my friends drive recent Honda Accord or Toyota Camry but have never gotten any MAF-related problems. They are the kind of people who would never open the hood to check for anything, except taking their cars to shops for scheduled engine oil changes.
3) Many people on this forum (especially Mr. LarryBible and some other die-hard MB afficionados) really hate Japanese cars for having timing belts instead of timing chains, but I have to tell you that replacing timing belts + water pumps on Japanese cars only costs around $200-300 (labor + parts) in many Asian shops in California. These shops are usually much cheaper than dealerships or indie shops owned by white Americans. So my friends just have to replace timing belts + water pumps every 120Kmiles and they're ready to go at least another 100Kmiles or much more without any major problem. BTW, the only reason they replace water pumps is to save labor cost at the same time when doing a timing belt change. Water pumps on Japanese cars surprisingly last much longer than those found on German cars (MB, VW and BMW).
4) I think the only exceptionally good thing about Mercedes cars is that their body structure integrity and suspension seem to be quite better than Japanese cars when they are both old and have high mileage. I feel very safe sitting in even a very old Mercedes.
The above-mentioned things (1,2,3) do not apply for old Mercedes diesel cars. I always love them because of their legendary robustness and reliability.