To paraphrase "I was buying cars before JD Power was in business."[:)
I have never depended on a company based survey to buy anythng.
The responses are based on subjective interpretation of vague meaning. A person who didn't read the manual (and most don't) finds all kinds of problems because of lack of knowledge and therefore provide low marks. The entire questionaire is made up of general information and does not get specific. How many cars and respondents are represented by their figures? How many repondents do not respond? Just how big is the sample? When a problem is checked...how severe was it, was it a problem at all or something caused by the driver?
The data for the the 2005 S Class for instance (they don't list the 2006 yet) states "score based on model year 2003 vehicles. Ratings for the 2004 vehicle may be different, and will be released in October." The data is out of date and they have not met their own update schedule.
Sure the early ML's and even my 2003 E320 model had many problems that should not have happened to a MB automobile. Ask Jerkin Schrimp (my name for the CEO responsible for this downtrend) how many dollars he saved with his cost cutting? BTW...my E320 was perfect and I did not have any problems with the car before I traded it for the S. How may other have had a similar positive experience...we will never know because JD Power only reports the negatives. They don't report the positives, only the number of reports per vehicle, regardless of the nature. A complete breakdown on the highway counts the same as a blower motor that makes too much noise. Which is the more critical?
My 2006 S is what I would call "flawless" at 4 weeks of use. So what do I need JD Power reports for...nothing. If Lexus is first on the list, and one thinks that Lexus is the "best" then go buy a Lexus. I will take over 100 years of great carmaking ability and ignore data that may or may not be valid.
You can believe their PR
and base your purchase and opinion of any car on their reports or you can do your own research and make a personal detemination. With the internet now it is much easier to research a vehicles' plus and minus factors and come up with some specific conclusions about what to buy and not buy.
So I guess the short answer to your comment is...I have never concerned myself where MB was in the JD Power surveys....