Longer boats seem easier to roll. They don't swirl around as much when you are setting up. The Ammo is an awesome boat if you already have a good roll and you already know you like paddling something with a shorter bow because of its ease of manueverability. Stable, but you gotta know those edges. It forces you to learn good boat control, which is good, but be ready to do some rolling as a first boat. Really fun for paddling aggressively, surfing, spinning, and crazy stuff like looping HUGE, and freewheels. Also fun for familiar runs, grabbing tight eddies, like a play boat with some body armor.
The Burn makes it easier to route through whitewater and roll. And has a dynamic design with softer edges, that makes it easy to drive and accelerate through rapids, rather than just float through. Which can be really important when you are trying to get to where you need to be in whitewater. Good example is the Pine Creek rapid on the Arkansas in Colorado. You like those edges when you skirt past that bad boy!
Your height and weight, Medium Burn. AND I paddle Medium Burn on everything and I weigh 145 5'4'' and put a little foam under my seat. When you outfit the boat try to imagine paddling and keeping your elbows from hitting the cockpit rim and your knees up past the thigh braces. Hope this helps.
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