It really freed up the door speakers and tweeters to do their thing. It doesn't sound like the premium system in my Audi, but it's really good. That sub is just right. Quite a bit of bass and it's really clean. It has plenty of boom. I'm running it at about 30% right now. Anything above that is too much. I don't listen to my music super loud, so it's plenty for me.
I don't see myself doing any more tweaking to sound at this point. Just thought I'd let you know in case you're still trying to decide.