I have a Nismo and I had to put foam tape everywhere on the hatch plastic. I put them throughout so to minimize plastic to metal contact. I also wrapped whatever wires I was brave enough to do (defrost) w/o snapping the wire). I still have a little rattle when I turn the bass and sound all the way up. My woofer is pointing up like you're s. I have no rattle inside, however it's a very minor rattle outside. I do mean minor rattle.
I would have to say from personal experience that it's all about the setup and how you prep it for the intended purpose. You want bass and not sound like ****? You have to put time, money, and effort to prepare the area to take the sound.
