When I bought my 2001 ML430, I was later horrified by all the negative press and owners problems with this rig......I was sure I had a POS rig.
11 years later, 163K miles the following is what I have to replace on the ML:
Spark Plugs (once at 100K miles)
Air filters - 4 times
Oil and oil filters
Bottom line its been an excellent rig despite the bad press and owner issues.
Why is this is.....because people are more inclined to jeer than to cheer.....even on enthusiasts websites.....by the way CR gets their reliability data from owner surveys.....referenced the "jeer than to cheer" statement.....ergo skewed data sets.