maiklsl63

Hi all, i own an S63 Coupe M157, 2018. I am one step away from obtaining an Quantum tuning ECU tuning and i have two questions and i would really appreciate the answers. Q1: i have removed my cats, and i have installed K&N air filters on the car, so that should be enough to try a stage 2 or shall i stay with stage 1? Q2: any recomendations/observations about Quantum Tuning? they seem legit, but i would really like to hear opinions here.... thank you