Is E/C43AMGs more of an AMG than M340/M550i's are an M car?

Don't really care about the labels, but seems like these "M-lite" or "53 AMG" trims are the only way you can get a slightly upgraded performance or a six-cylinder engine on certain models nowadays.

I'm not interested in a full fat M or AMG car, but interested in something more potent than a turbo i-4. So curious who actually executes it better between Merc and Bimmers.