The 43-inch Orb octabox ($130) is deep and lightweight enough to Velcro to a lightstand, where it can accept many monolights or any shoe-mount flash. It produces circular eye catchlights, and the output can be softened with the included diffusion panel. For $70 more, you can add the extra light-focusing ability of an egg-crate-style grid. It's not the cheapest option available, but it's durability and adaptablity make it a solid buy. It will get used.