I would seal it up and run the Icon in there. I just put an Icon 10 in a 1.03 cu ft sealed box with a double baffle and some bracing in the back of my Accord 2dr and it sounds amazing. I thought about getting the Gcon, Im running 1K watts and I liked the idea of the Icon being rated for more than Im running. Id rather have something over-rated and leave myself with some headroom later, and peace of mind knowing Im not pushing it to its limits. Im sure either will sound great.