These are my first long bladed fins. I dive in Lake Mich so sturdiness is very much a factor - likewise surface cruise. I wear a 10.5-11 shoe - usually 11. I've read through alot of posts on the forum but am hoping somone with strong opinions could drop a post or two in. I can get either fin for $100. Up till now I haven't used a boot with my fins and I'm wondering how the longer fins differ in terms of how they should fit etc.