Boxes perform as good as other reviews have stated. Fit perfectly in my 2024 GMC Sierra 1500 crew cab. Boxes came with two metal brackets to hold them together, so sliding around and visible gaps were not an issue. I installed Sundown SA V2's with no fitment issues in one box, and a little shaving needed in the other to the MDF around the magnet extension, but very minimal. The front of the boxes do not have gaps at the floor for sound transfer, but rather at the back of the boxes. The sound moving around the back wall and glass sounds incredible, and my kids can't spill crumbs under the sub box which is a nice bonus. The magnet extensions do sit high into the rear seats, and you can feel them when using the seats, but worth it to have this large of a box in a crew cab. Well worth it if you want deep bass in your truck!