Things I'd be concerned about are items that are subject to shock damage such as suspension and odds and ends like the xenon levelers. When I sold my E46 M3, the guy ran over a pothole the next day and had to replace the above items.
I've hit some nasty potholes, and they always sound a lot worse than they are. I've never had a situation where ground clearance would be an issue, but it would have to be something pretty stubborn to do damage to undercarriage components.
///M Power - 2011.75 LMB M3 6MT (fuelly)