I've had my Borla for a few weeks and I love mine. It just keeps getting deeper sounding.
My wife and daughter say it's too loud, I just smile (it is MY car). At first, I kinda caved in to them, now I don't care (again, it's MY car). Everyone gives me thumbs up and tell me they love the sound, including neighbors...
I have noticed the sound change as it breaks in, making it sweeter sounding than before.
Like most things in life, it's a trade-off. I WOULD DO THIS AGAIN!!! But realize, it is louder