I was looking at some cases that I could buy and came across the Fractal Design Define R5. I loved it. It had two 5.25 inch drive bays hidden by a door, perfect for what I need, plenty of space, and excellent cable management, not to mention the build quality. But there was one problem, and that was the side panel window. It's little. Later I came across the Define S, without the all-important drive bays, but has a huge window. Everyone says that the R5 panel can't go on the S, but can the S window go on the R5?