Since you're lower and closer to the water, Masters says the Bellyak gives you greater stability and agility, and there's no need to carry a paddle with you. (Or risk losing one in the churn.) You propel yourself with your hands (and a pair of webbed gloves), like a surfer paddling out to the break. Strategically placed handles let you hang on during wild rides, and perform tricks in less rapid waters.
So, I asked the folks at Bellyak the odds you'll drown swallowing water coming up over the nose of the Bellyak. The answer: Pretty slim. The boat is designed to channel water up and to the sides, keeping your lungs water free. But you will experience a good amount of splash, "all part of the fun!" they told me. And my next question: "How often do you smash your face on rocks?" was answered the same way, the long front end keeps your mug from meeting stone. (But like any extreme sport, it's recommended you wear a helmet.)