I've busted a rib as well not using an impact vest, which taught me to use them more. I have tried the Airush vest, which has a nice pocket in the front to carry goodies in but the thing likes to ride up after a while. So I got the latest Dakine vest which costs a tad more but has a better fit. It doesn't have any pockets. This one also rides up after riding a while with a seat or waist harness but not as bad as the Airush vest did. Probably has something to do with my beer gut that pushes it up too.

The Dakine Matrix is pretty sweet and stretches to fit really well.
We also have the NPX Cult Wake vest which doesn't have a zipper. Both are really nice.

http://www.oceanextremesports.com/catalog/cult-wake-impact-vest-p-925.html