Ok so I finally got around to installing the Kenwood KSC-SW11 under my passenger seat and love it. It doesn't add a crazy amount of bass but it is very noticeable and rounds out the sound very well. I'm very happy I added it and it was very cheap. Installation was pretty simple and I even managed to run all the wires under the carpet so its hidden very well. I used information I gathered from other threads as too which speaker wires to tap into, using a fuse tap for the remote wire, and where to come through the fire wall. The only trouble I had was removing the pastic trim on the rails I tried to remove it and ended up cracking it
. After I got the plastic rail off i realized it was much easier to just remove the weather stripping and use a flat head screw driver to pop the pins that secure the plastic rail into the frame. I tried to look for an OEM replacement online and had trouble finding one. If someone could help me find the part so I could order it I'd be super grateful. I hate having a crack in the trim on my new Fist =(.
Heres some pictures compareing the kenwood to the kicker. the Kicker ended up being to big to fit under seats. I also added some pictures showing how well the kenwood fits under the seat and theres some pictures of the trim I cracked. its from the passenger side and hopefully I can get a replacement part.
http://imgur.com/a/cZOF2