I really don't see the similarities between the two, besides their names. John Vignocchi seems like a genuinely smart and cool dude, while Jean-Ralphio is meant to seem ditsy and unlikeable. Also don't think John could ever pull off Jean's hair.
They carry themselves similarly. Not saying that Vignocchi is incompetent, just that his business guns persona that he puts on sometimes coupled with his appearance and smirky grins totally remind me of Jean-Ralphio.