I've used both, and both have pros and cons. Snaps can be tough to close sometimes and can pop open as well. However, when they work well, they work better than Velcro. Velcro is easier to fasten when your are encumbered by plastic, but it isn't always the strongest. Snaps were used in ANH and ESB whereas Velcro was used in ROTJ. If I were to build a suit today, I'd use snaps.