I have a nameless axleback delete on my STi, I think it is very loud on cold starts. On weekdays when I leave early to work I roll the car down the street and start it there so I don't wake the neighbors. Then I sit by the lake to let it warm up.
Even when I pass people on the highway I am mindful if they have their windows down I'll pass at the lowest RPM possible.
I did that even with the stock exhaust. And I frequently ask my neighbors if the noise has bothered them at any point. No need to be a dick about it, the car is loud and just because you enjoy it doesn't mean everyone else does.
A little courtesy goes a long way.