Delighted with my Mercedes SLK 280, in Mars Red. I fell in love first with the styling, then with the drive. My favorite part is the air scarf and heated seats, that let you drive with the top down in cool weather (which in Texas is just about year round). The hardtop is leaps above having a rag top and works very well (and impresses anyone who sees it). I actually like the factory nav system, and it has worked well for me. I find the car very comfortable on road trips, and got about 32mpg on the highway with premium gas. My car has the DVD-based sound system - 4 GB of MP3's is a lot.
The hardtop convertible, the air scarf, the heated seats, the sound system, the front end, the back end. Turns heads.
The owners manual needs work. The GPS could use updating. The cruise control knob is confusing (like most MB).