If you don,t want cabin drone then don,t fit Cobra (either type )
I had one on my roadster and it sounded like one of those boy racer Subarus.
New car has the Gemini Invidia .with Cobra hfc,s Expensive system but a much more "civilised " sound with no noticeable drone up tp 3500 rpm.so cruising is better.Obviously this is my opinion....undoubtably,others will disagree.
Not necessary for other drivers to hear you coming ..just to hear you leaving them.