Here is a comparison of the internals of the 3 big tenkeyless boards that are discussed here at Geekhack: the Filco Majestouch 2 (aka MJ2), the CM Storm Quick Fire Rapid (aka QFR), and the Leopold FC200. From the outside, the similarities of the MJ2 and QFR case design are obvious. They are both made by Costar and therefore use Costar stabilizers. However feature-wise the MJ2 has an attached cable and separate caps/scroll lock LEDs, while the QFR and Leo have removable cables attached from under the case and integrated LEDs. The Leo uses Cherry stabilizers. A nice touch on the MJ2 is rubber feet on the rear legs.
The MJ2 and the QFR use the exact same method to support the plate. The plate is curved downwards at the top and bottom, which rests on the base. The plate thickness is the same (0.055") and both are made from steel. The cases are the same material and about the same thickness (~0.110"). The only interesting difference is that the MJ2 uses 2 screws to hold the plate down on the base. Both clamp the plate to the base with the top half of the case, which snaps together in the same way and are locked together with one screw.
The Leo, on the other hand, has a plate that curves up and is supported by small ribs along the top and bottom. The plate thickness is the same, though, so this probably does not affect the feel of the board in any meaningful way. The case uses slightly thinner plastic, about 0.100" - 0.105" and snaps together with small tabs along the bottom edge (which make it much easier to open). It's locked together with three screws.
The QFR and the Leo use a single-sided FR2 ~0.06" PCB while the Filco uses a double-sided FR4 0.065" PCB. The MJ2 and QFR both use a header-mounted controller (though not compatible) while the Leo has the controller built onto the main PCB. The slightly thicker and denser PCB material on the FJ2 is the only major thing that sets it apart from the other two.
