The retractable hardtop is nice. It is the first convertible I've had that doesn't leak. You'll need some Gummy Fledge (tm) to keep the seals from squeaking. The interiors are very similar. The interior is nice. The supercharged 4 banger is pretty torquey for a 4 banger. I believe the SLK rides smoother due to having shorter wheels and more sidewall. I have not compared myself though.