We took it for a drive; wow, it's a really nice car, so we're probably going to buy it. We saw a note from the previous dealer that said "run-rough AT", but shifting felt perfect, should I be concerned? Here's the description, any suggestions or warning?

2008 Mercedes-Benz ML350 4MATIC
Mileage 91,028
Engine 6 Cylinder Gasoline
Transmission 7 Speed Shiftable Automatic
Drive Type All wheel drive
Price $21,995

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2008 ML350
2007 Honda Element
2007 Honda Accord
2009 Honda Civic