Just got finished installing the subs. Here's the good, the bad and the ugly.
First, I want to say it is nice of Bavsound to provide an installation kit. All the required tools were included and made the install very simple - no need to search through my toolbox.
The improvement in sound quality is tremendous. I was a bit worried at first - when I removed the stock subs and compared them to the Bavsound, the stock ones are substantially heavier, even despite that Bavsound subs have a metal grille. Despite the weight, they sound at least twice as good as the stock, and I'm very happy with the improvement in sound.
However, they are not as plug and play as I expected them to be. The stock subs are contained within a plastic enclosure that mounts underneath the seat, and the plastic grille mounts to the enclosure. When you install the Bavsound sub into the enclosure, the top portion of the enclosure does not fit, so you can't mount the grille, and sub is exposed underneath the seat.
This is what it looks like right now. I am thinking about maybe even just gluing the grille to the carpet.