[mjposner]

I have been through similar issues with a German car, and I think the dealer and BMW are treating you well. You got a nice loaner (worth as much as a 65k 2012 M3), you obviously pile on miles so you are saving miles on the Mercedes and the BMW M3, they fixed the car for free and gave you a gratuitous $1,500 which they were under no obligation to do so at all. Cars fail, its a fact, and some failures are partially the owner's fault. You could of accidentally tried to close the top with something blocking, slightly warping the system, causing the leak...Some owners over rev or do not wait to warm up, some fail to follow the initial break-in period, and some cars are built poorly (they save never buy a Monday or friday built car...). The engine costs $24k and the install is 9k (at least that was what I was quoted when mine was flood damaged). So you more than got your extended warranty back. I hope all ends well and in the end you vote with your wallet.