Where should I Mount My Sub??

I have a double cab with a 10" kicker in it. I've had it in there for about 2 years now and it sits right behind passenger seat on the floor but its annoying for my passengers and it takes away from the clean look on the inside. *********.com offers a box ($157.45 w/shipping) that replaces the storage bin behind the drivers side back seat. Do you guys think that that would be fine or does anyone have any other ideas, or places to get the same box local? Will I lose sound quality by putting it behind the seat? what about under the seat? so many questions so confused! please help!! want to get this process moving as fast as possible. Thank you!!!!!