The most important models, like the S class, the G class, and the AMG GT, still are the top notch in quality, quirks, and performance, but the other aren't like

The most important models, like the S class, the G class, and the AMG GT, still are the top notch in quality, quirks, and performance, but the other aren't like that C and CLA class models are more like any other regular car with a nicer interior and maybe a better suspension, but at the end they even Renault engines (that aren't so well made), so they aren't so great than older versions. All of this is AFAIK, so please correct me if there is any mistake.