I had an SL55 and really liked it. Bought an SL63 for my wife last year and I gotta say....I am more impressed with the car every time I drive it. Very fast, comfortable, sporty, good exhaust note when you get on the loud pedal. Sporty. I really like it a lot now.
I think the AMG cars are very impressive. I have an S63 for when I need more than 2 people to transport and that car rocks too.