I mostly agree with Lebenz. Although they won't warrant a problem with a 8 year old 100,000 mile car, they still do a good job in the good will department WHEN COMPARED TO most of their competitors.
Case in point, the Trap Oxidizer problem of the '86 and '87 diesel cars. As late as about two years ago, MB would replace the ENTIRE EXHAUST SYSTEM when one of these cars came into the shop. This was sometimes done without the customer even asking for it.
Case in point, the wiring harness problem of the M104 engined cars was taken care of long past the warranty limit.
They might not be taking care of the evaporator problem on this long out of warranty car, but their track record is better than their competitors as far as taking care of admitted engineering blunders.
I know it is a bitter pill to swallow regarding the evaporator, but how many new MB car payments can you make for $3,000? Not many. If the rest of the car is in good shape, you would be well served to replace this evaporator with an improved version, swallow hard and enjoy the car.
Best of luck,