Compare the Vauxhall-Opel GT 1900 - [1968] vs Mercedes SL Class 190SL W121 - [1954]. Find out which car is the fastest, most powerful, lightest or has the biggest engine in our top trumps style comparison page. Find out which car has the highest top speed or is the fastest accelerating, is it the Vauxhall-Opel GT 1900 or the Mercedes SL Class 190SL W121. We'll leave it up to you to decide which is your favourite.