Yes but it was more of an in-house deal. My father bought the extended warranty on his '00 Silverado which took it up to 100,000 miles. I bought it from him at 99,750 or so. We decided he'd take it to a dealership to have them find every tiny little thing wrong with it. When we got the laundry list of nothing real major except a minor item requiring replacement of a universal joint
and some items related to the 4WD system we took it back to the dealership where he bought it and just bought a shiny new '05 Silverado at the time.
They fixed everything under the warranty free of charge and even threw in an oil change because they noticed that he was entitled to a free one he never collected after originally purchasing the truck 5 years before. I'm still running the original brakes from 2000 and they're not even halfway worn yet. It's amazing!
The warranty is expired and at 115,000+ miles I have a great running truck that burns entirely too much $3.00+ gasoline
Back to the point in this case yes we did see the return on the investment with the warranty. Like you kind of said...piece of mind isn't priceless but I wouldn't want stuck with a big bill later when I could have paid a small one early on.