FWIW if I had EFI on my Duster I would seriously consider putting in some high-flow cats. The smell of pump gas fumes just gives me a headache nowadays; but race gas, that's another story of course lol!
I agree about the fuel being burned as it relates to the fumes. I am running this car on 91 octane California pump gas, and the fumes are obnoxious. My 1970 E-Body burns 101 octane Street Blaze. Those fumes smell wonderful. I get compliments on those fumes all the time.