lol all the main online searches came to engine displacements being bigger the 3000cc
http://www.street-car.net/forums/showthread.php?t=2

Issues with the W210 that I know of:

1) Certain V6 engines have the harmonic balancer problem. There was a recall/service campaign bulletin about harmonic balancer failures and a replacement schedule. Affected cars include W210s from '98 - '01 with 112 and 113 engines. Which equates to a heck of a lot of cars. Some cars outside that range also were affected. But basically, a harmonic balancer failure while the car is in motion is a very expensive problem.

2) Blower motor regulator for the A/C tends to fail after a while too. Apparently this affects the earlier batch of W210s, and in this country, it's not a good thing.

3) Rear electric window regulator failures x100000. The palstic gears get mashed up and the window falls into the well. Have to replace the entire assembly.

4) Suspension ball joints wear out at an alarming rate, especially on the Avantgarde spec with the lowered ride. Looking at maybe 50k too, but you may be able to live with the lower tolerance if you drive sloooowwwlly and carefully. In our pothole country, good luck.

5) Mass air filters/ 02 sensors have to be replaced at maybe every 50k.

6) Talking about sensors, there are a lot of warning lights that pop up. You'd find that many have the letters ABS/ESP/BAS and such. Problem is the brake light switch, and if not, then the actual accelerometer at the wheels.

7) Rust. Anti-corrosion wasn't somethign MB took a lot of care of during the W210 era. Always check the car super thoroughly for rust. Especially, look at the wheel wells, and around the suspension components.

8) The Infamous Steering Wheel Squeak. Quite possibly the most annoying issue possible.

9) At every 100k, you'd be thinking of a piston ring replacement, and motor mounts.

10) At 150k, you'd want new rotors too, cos new pads won't stop the brake squeal.

11) Transmission: worry about this. At 150k, some other Mercs would be begging for a tranny overhaul.

12) Others: wheel bearings, cats, deterioration of internal plastic parts, failure of electric seat motors, air cond vent vanes breaking, rubber button coating melting into a sticky mush, interior light failure and yeah, rear brake lights burning out and melting out the brake light housing.

While many of the problems above are faced by many W210 owners, not all affect them. My regular merc mechanic says that he sees a lot of the above in W210s, there are some particularly problem-free ones. Ultimately, it also does depend on how spirited/careless the previous drivers have been.

However, you can't discount the fact that this is a premium auto, and carries premium features, which upon failure, demands a premium bill. The W210 came in a time when really complex electronics were first making their way into regular passenger cars. So if you do decide to get one, jus tbe aware of the costs involved.

Also, W210s are kinda underpowered and severely wanting for a 6th gear....

Edit: this post was't actually targeted at the person quoted, more towards those thinking of owning a W210.