While waiting for countertops, I'd put a 4x8 sheet of plywood on the island so we had some place to put a microwave, toaster oven, coffee maker and a small camping stove. This what happened when I went to unplug the microwave to move it in preparation for the countertop install. The filler panel between the backs of the island panel popped right off. All those kerf cuts tell me something isn't straight and will have to be corrected.