I have seen this service bulliten also, and like you have seen 4-5 cars with this complaint. If you have a scan tool that reads live data steam in the LH-SFI system, look at the fuel trim readings, if they are below .930 then you have verified the problem( which is the engine is running too rich ).
I have had all but one person dig deep into the wallet and correct the problem, it is a shame that the problem did not occur when the car was under warranty.
Please, let us know if you find any more interesting TSB's.
14 year MB tech
7 year shop foreman @ independent MB/Volvo shop