I've been looking at making a sealed sub box and was wondering what is more important: cubic volume or dimensions? What I mean by that is if a sub company recommends a 1.00 cubic ft box does a long box that is shallow vs a box that is more uniform effect sound even if the cubic volume is the same?

 

With a sealed box, you are after volume. Dimensions are only important for ensuring the sub will fit. But there are some considerations to keep in mind. If you do a long shallow box, it will require more bracing than a square box. So make sure you take any bracing into account for your volume as well as the mass of the sub.
I created a sealed box for a Jeep. The box was really shallow as it had to fit between the seat and a storage box in the rear. As the sub was over 7" deep, and the box was between 2 and 4' deep where the magnet was, I had to build a square extension to house the magnet. So you can build it any shape you want, especially if you are working with fiberglass.

 

Thank you for your answer!!