Most of the reason why people have bigger boxes in there car is cause your suppose to have the right amount of cubic inches on the inside of the box to get the best sound out of the sub. My boxes are pretty big and they take about half of the room in my trunk and there heavy........but they sound great. I have two 12's

If you buy a box made for a 10in or 12in then it should sound good cause im sure that the company makes them to the right cubic inch. A custom made box will have to figure out the right amount of cubic in