Very nice, thank you for remembering tlronin. I really like the idea of having each tray double as a display unit, which in turn could be added to others for a larger diorama. A friend of mine has a similar set up for his CWE, but uses much bigger sheets that slide in and out of an old camera/projector case that is huge and weighs a ton. But his sheets aren't based at all.
These ones are a very convenient size.
Cheers.