I'm rather partial my stainless steel case, but I don't expect to be running another GB so your best bet on that route, is to get the .dxf (I think I posted them in one of my threads but both the ergodox thread and I think the CAD resources thread have them too) and get BigBlueSaw to cut you some 1/16th" SS.
Major advantage of a SS plate is you can use plate mounted cherry stabilizers. I don't think the Ergodox PCB supports PCB-mount stabs & I hate costar.