i dont want to type out everything but i have worked in shoes stores for 9 years now and am a sneakerhead myself, i currently work for new balance but if you name a shoe i can tell you pretty much everything about it, i am a certified pedorthist as well so i can make insoles and shoe modifications. I know how to fit shoes and the type of support each style has. PM me if anybody has questions on fit and support.
With that said the nike free's are awesome for someone that has a high arch and doesnt need stability(most teenagers) extremly light weight and comfy, i prefer the nike air zoom hayward 3, very similar to the nike free's but it has a full length zoom air cushioning. Any questions PM me.