The rescue vest in trained hands is a very handy device. The most important feature of a rescue vest is the quick release system which regular PFD's lack. You should never attach yourself to a rope without some type of quick release system as this can be deadly. Take the time to learn how to properly use your rescue vest and thread the belt so it can quickly be released.
Rescue vests have gotten significantly less expensive these days, most sell for roughly $200. These vests typically have more flotation, extra pockets and tie-downs, and most important - a quick release belt system. The quick release system is the most important feature of a rescue vest. If you need to replace your current PFD, I would strongly recommend upgrading to a rescue vest as it is so much more versatile in use.
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