Wall it or not?

[superdave07]

ok heres the deal, ive never done a wall, im more than sure i can build it correctly, but im not sure how it would sound, ive never heard a walled car. Some vans and stuff but im talking like 15 12inch subs and etc... im doing 2 dc 4xl 18s in my hatch, behind the seats. i have more than enough room for a wall, and it'd be tight but enough room for a traditional style box behind the seat. so im on the fence here. Anyone have any input for me at all? I want it to be tuned low, do hair tricks etc...not going for numbers at all. but i like to be able to listen to a song also not just hit one good note. Any input would be great guys!

Thanks in advance...