Compare the Mercedes 300 SEL 3.5 - [1969] vs Mercedes SLC 350 C107 - [1971]. 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 Mercedes 300 SEL 3.5 or the Mercedes SLC 350 C107. We'll leave it up to you to decide which is your favourite.