The R129 has always been my favorite of the SL-Class, even more so than the Gullwing. It was the absolute last of the old-guard Mercedes automobiles before the bean counters wrested control of the company away from the engineers, so they were built to last 1 million miles before even requiring a tune-up. It was even built on a shortened version of what was the absolute peak of Mercedes-Benz's traditional, gloriously gratuitous engineering, the W124 platform; which means the only way you will ever break anything on it is if you crash it into a bus. So it was like a W124 convertible, only with newer, more powerful and larger engines. And they looked fantastic. A normal 500SL, or even a 300SL, would easily be a Cool.
Then AMG got their hands on a few of them and put some Pagani Zonda engines in them (yes, I know I have that backwards). It was like a more contemporary, convertible version of the AMG Hammer from the mid 80's. Only with a 150 more horsepower. Absolutely, fantastically Sub-Zero.