I have that 12" center seat box from E-bay. It does sound real good, but I wouldn't call it a stock appearing replacement. It is a rectangle. A very squared off front corner, the fabric is a lot lighter color than by Agate 2002 interior (I sent numerous pictures and the color codes with the order).
I knew ahead of time that it would sit up over 2 inches higher, and certainly does. Makes my six-speed shift knob almost disappear in front of the console. No chance of fitting a Geno's cup smoothie on it, dam. It also leaves a pretty good gap between it and each seat.
Its great for the price, $150. I just thought I would share some of the real world differences. Would I do it again? Yea, but the JL stealthbox uses your factory seat cover which guarantees it looks stock. And the cover is real easy to change. i would think about it a little harder if I had seen how it really looks.
P. S. the 10" box sits lower and would hide a lot of the above issues.