I stopped buying UD e/s last year because I felt like I was getting too old for the shimmer/glitter. But now that the mattes came out, I am so tempted! Did anybody get in on the vault deal? It's so pretty online.
I got the vault-unfortunately MAC shadows are too small for the holders! I'm bummed too-but I have so many UD eyeshadows that I've almost filled the vault so at least I got all those out of my makeup train
The bottom isn't magnetized...so magnets wouldn't work. You could try the tack though, although you put the whole eyeshadow pot in so you'd still have to lift the lid to use it.
I'm actually considering taking my shadows out of it because I store them in a different place than the rest of my makeup so I keep forgetting to use them. It's kind of sad. Anyway, I'd say the vault is pretty much a waste unless you really need some sort of storage for the shadows.