If I turn my radio off I can hear mine a bit. Wouldn't describe it as drone, but you hear the exhaust cause it isnt choked up. If I have radio on, I can't even hear it at steady state throttle. The only thing that bothers me is when running in D, you can hear a gurgle when the DFM kicks on and off. It's most noticeable in hilly or windy conditions cruising at highest speeds. I suspect that would be the case with most of them since you remove the flapper.
My wife's only comment "is that why you always want to drive so you can race everyone and hear that exhaust"........ "and you wonder why the boys are like that"..........she doesn't complain, just smiles and shakes her head.