the only thing u have to worry is how are you gonna put stuff at the boot w/o damaging the driver? and oso, where will the spare tyre sit?

it looks unique though.. but since u saz not gonna put anything in the trunk, why not get a wooden box enclosure?

although i'm no expert, but wouldn't bolting the subs to the car floor will somehow affect the chassis too? slight vibration to the chassis?

but, the vibration *might* be a desired property...