I've been a Benz fanboy all my life, which is odd, because I drive a Lexus and I'm buying a BMW. In my opinion, it's not really fair to compare the SL to an M3, or to any car really. There are not hard-top convertables that are as perfectly proportioned as the SL. The lines are beautiful; top up or top down. The other verts just don't look as good as their coupe cousins. Maybe its because we've never had an SL coupe to compare to, but I don't see any convertables beating it any time soon. The new Ferrari hard top convertable looks great with the top up, but its rear is pretty terrible, and with the top down it loses 50% of its good looks.
As far as performance, its pretty obvious that in the end the SL will not, and could not, match up with a car that was designed the way the M3 was. The SL is a tank with a big engine and a sexiness to it that is only matched by Aston and Alfa Romeo's new 8C. Despite the cost difference, its still going to get trounced around a track by an M3, but I imagine most SL63 owners bought the car to look good, anyway.
I agree. Good for looks, but you can do better on driving enjoyment. SL for the beach, M3 for fun, and your own pick for your daily driver. (I'd go with a Nissan Titan
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