I've got a corsa sport on my 5.3L paired with an S&B intake. My BBP tune took care of the chop from the AFM, and honestly I can hear my tires more than my exhaust. Living in Hawaii, I pretty much go through hills all the time, and with the AFM on, it felt like I was piloting a helicopter rather than driving a truck. Towing with my truck, you can definitely hear the exhaust note a lot more, however it's not excessive.
Do you have pics of it mounted in your fuel door? I'm debating on whether or not I should get this, and I'm thinking of out of sight places to mount it.
It typically doesn't exactly bother me, I'm more or less curious if this is a common thing or whatnot. However it's been roughly 5 times and I'm at 8k miles.