mc061680

I just got Rohana RC7 rims for my 2013 CLS5504matic. I don't want to go with 25 profile in the rear. Stock size tires are 285/30/19. If I go 275/30/20 I'm still within 3% difference from stock, just not sure how would the 275/30 tire look on a 10" rim. If I'm running 285/30 I'm 3.4% difference from stock. Would that be still ok considering 4matic? Please help!