Yes i have a few kits that have not been used but this MOC has forced me to look through my stash. I always mix and match. A challenge for me would be to use just one kit for a layout. I never do this lol.
I had to laugh when I first read this, I probably have 15 or 20 kits that I had to have at the time but I have not used yet. I tell myself I'll use them someday. MOC has certainly helped me use more of my stash, but there are still quite a few in this category.