Tony I can tell you it does not change the sound as a matter of fact to me it sounds better then the stock as long as you get the active exhaust kit with the aftermarket exhaust. I compared my Bullitt with a stock Bullitt and I have no regrets there is a difference. One thing I would say is my stock exhaust was all rusted out when I looked at it when it had only 600 miles. It looks like that's the way it came from the factory and those tips were faded out black going to gray.
Joe
Hi, Joe - on every video I've heard, either the pitch of the tone or the volume sounds different than what I hear from the stock set-up, even if it's just a bit. The one combination that I heard that was closest to it is a
new Borla X-pipe that replaces the resonator. Of all the aftermarket manufacturers, I've often appreciated what Borla can do in terms of their engineering capability - they seem to get the "music" aspect of sound tuning, especially in combination with the factory set-up. I am not dissing anyone's choice of sound or engineering prowess of various companies, as exhaust sound a very personal thing. However, I can't justify spending the money on changing a sound in this car because the Ford engineers pay a lot of attention to this in the Bullitt. I've felt this way about the previous Bullitt Mustang models that have been produced ('01 and '08/'09).
A couple of provisos in my observations on the '19 Bullitt...1) sometimes what exhaust sounds like in person vs a video can be vastly different, 2) what an exhaust sounds like when the car is in motion vs not moving is different, and 3) I don't know how much influence there is of the sound enhancing technology for sound coming into the cabin when someone changes the stock system.
Some might lament there is more technical complexity in the exhaust set-up than past days, but the fact the engineers take the time and energy to try and capture the sounds of '60s era cars with today's regulations and constraints is very appreciated by me.
Sorry for the long response - the sound in the Bullitt Mustang is one of those "don't change" things for me

It's good that you find your experience to be positive with your change!