Hello,
I think an extended warranty is the way to go. With 70,000. mi. issues will turn up. I purchased an extended lexus plat. 7yr 100,000 mi for my 450H.
You can shop for a good deal. My brother, has a S550 Mercedes and he saved a bunch over the MB Plan by going with AAA.
http://www.autoguardwarranty.net/?zip=10011
Its very reputable and the price is very decent. Be carful most extended companies are frauds and will be out of business before you can use them.