All I heard about that 48 Valve V-12 is the maintenance cost. But, then again I doubt that you'll find a V-12 that is easy to maintain (later models at least). Think about it, that engine is similar to the engine that they put in the CLK-GTR
(or so they say)
However, when I get enough money to buy .. say a used R129, I think I'd shell out extra cash for the SL600 just because it's a V-12!
Any pictures of yours?