The '02 Silver arrow SL ( still a R129 ) was more of a tarting up of an old car than being an increased performance special edition. On the used car market I don't consider the silver arrows cars to be worth much more than a similar year standard or Sport spec car.

The SL 300 , 320 ( I 6 ) and 500 ( V8 ) are right around 4,100 Lb, the SL600 ( V12 ) is 200 ish lb more.