While I argue every modern turbo Mercedes may be a great tuner car, for example a 2013 or 2014 GL 450 can be tuned to nearly 500HP from it's factory detuned 350HP as it is a very similar set up to the GL 550.
That being said, there are some favorite Mercedes models to tune. Many actually start life pre-tuned as Mercedes-AMG models and go from there.
This 8/2020 list is based off of talking to sales associates at Mercedes Euro Motorcars (Aki says wagons are hot, and I've heard black S63 coupes are too), search volume, and forum research.
Popular Mercedes Cars to Tune
- C63, C43 Coupe and other variants
- G63, G550
- E53, E55, E63 Coupe and other variants
- CLS 63, CLS 550
- AMG GT and variants
- S63, S560, S550, Coupe and other variants
- CL600, CL65
- SL63, SL 600, SL65
- GLC 63, GLC 43
- GLE 63, GLE 550
- AMG GT 4-door
- Smart Brabus
- I know it isn't technically a Mercedes, but people like tuning them with Brabus parts according to search volume.