Yeah, I looked into it quite a bit. They all suck. There's no room for anything with enough throw to give low frequency response that doesn't sound like crap. They mostly just vibrate when given substantial power more than they project sound. If you want your car to vibrate with the beat, underseat works. If you want to hear bass, you need more air to move around. I would argue that all car bass audio is crap, but best case at least is to give yourself the most airspace to work with. Trunk wins.
2015 STi: Still Stock
04 STi, 04 WRX: SOLD