David,

First, I'm not as accomplished a DIYer as most of the other folks here.
Second, the only MB points of comparison I have are W202 and W210.
Third, our S430 is the car which we can least tolerate downtime on while I'm shopping for tools, parts, etc., and it has therefore been mostly dealer maintained.

Looking through my service history (easy to do, since I maintain an Excel spreadsheet for each of my vehicles which shows what work was done, when, using what parts, who did it, etc.) I can tell you that I have only done a few things myself on this car (we bought it 5 years ago at 107,000 and have put 92,000 mi on it - we know the original owner). They include:

Oil changes, filters, cooling flush, spark plugs, wiper blades, etc.
Headlight lamps
Seat trim (over and over again, it seems)
Front Brakes
Accelerator Pedal
Blower Motor Resistor

It needs a lower left balljoint now, and I'm debating whether or not to attempt it myself. I do not own the necessary tools. It's more complicated than American cars, I think. The valve covers are leaking, which I will do myself when the weather warms up.

I think it needs the dealer's scanner more often than my other MB's, which has led to the dealer getting more of the work that I might have done myself.

The oil filter is in a more convenient location than any other vehicle I've ever touched. It takes forever to replace 16 spark plugs (had the correct tools in hand when I started, and had none of the problems other people have warned of).

As I think about it, most of the time I have spent on this car was tied up in futile and expensive efforts to adapt the car to bluetooth phones, Ipods and Nav systems. But that's a whole other story.

I like the fact that it doesn't have monowipers like my other MB's. What we like best is that I can put the driver's seat all the way back (I am 6ft. 4in. tall) and somebody my size can sit directly behind me.

Well, I've been goofing off long enough. I have to go out in the garage and button up from the blower resistor job (just did it a few days ago, and it seems to have fixed the problem). I don't like dealing with trim under the dash (related to that 6ft. 4 problem), so I don't close it up until I'm sure I'm done. Plus, Cartalk comes on in a few minutes, and I find that my wrenching goes by more quickly if I listen to those guys.

__________________
1996 C280 289K Traded
1997 E420 167K Traded
2001 S430 240K Traded
2010 E550 4matic 80K
2000 GMC Jimmy 198K Gone to Boneyard
2003 Camry LE 196K
2011 Mazda3 i Sport 31K