I use hook-it. It's more expensive but it's worth it to keep from flinging pads across the shop.

Plus I just really like how easy it is to work with and the fact that if you need to switch grit in the middle of something you can always re-use the pad without worrying about getting the sticky side dirty.

Of course wet sanding is a lot easier too because the velcro doesn't get weaker with water unlike the sticky.