After having used an elastic band for a while, I noted that I had to use one with the least tension possible to hold the props as I found the props were being subtly misshaped by having too much tension. I've never used, nor even touched one of those Lance Armstrong things, but they seem durable and determined to hold their resting circumference. That's great in most situations, but maybe not so great when bearing down on your device and props. It's something to think about, anyway.