I use Sorbothane for mostly everything (except my floorstanders). Many years ago I bought a 12" x 12" x 1/4" sheet off ebay and it's been great for everything. It cuts easily with a knife into squares that can be used as footer for bookshelves or under feet of components. It's also naturally tacky, so provides great stability - monitors will "stick" to the stands, so they wont topple over, but you can easily peel them off when needed.