I have a 1998 C280 Merc. I can buy an extended (complete coverage, $0 deductable) covering 7 yr/100K miles for about $1200.
Considering the cost of repairs, frequency of repairs, etc., is it worth it. I plan on keeping the car for quite a while.
(This is NOT a Dealer warantee, this is from the Amer. Auto. Assn).