Plastic hose fuel line parts. It is the biggest hassle with those cars. I like the 98-99 turbo. I work on a 99 regularly. We used copper anti seize for the new glow plugs. And purchased the reamer.

But I much prefer the W211. For a little more money you get a lot better car. I like the CDI better. Even the 99 feels old the 05 feels like a brand new car.

Just my two cents. Beside I run WVO in all of mine so my opinion is skewed.