I've had a pesky problem with a 2007 GL 450 where it won't turnover on occasion. It's one of those issues that when you're with the mechanics, it works just fine, making it very difficult to diagnose. Well, my service advisor John Cummins has been with me all the way. I've been provided a complimentary car (a new Mercedes with less than 2500 miles on it) to use as they trouble shoot and fix. When one attempt to fix didn't solve the issue, they gave me a full credit. It's now been resolved. The vehicle was out of warranty, and it did cost me something to fix it, but Schumacher really worked with me. It's this level of service you expect from a top dealership representing Mercedes, I got it.