I use Aeris Velocity X3 Spring Strap fins and personally I'm not to fond of them. They don't have much thrust or anything. and because they are so long they have little to no stiffness, so very little feeling of propulsion(or any propulsion for that matter).
They probably make them so flexible to reduce leg strain, but because of this they actually hurt more because you have to do VERY quick, long strokes to get propulsion, and it hurts like a mother!
They probably make them so flexible to reduce leg strain, but because of this they actually hurt more because you have to do VERY quick, long strokes to get propulsion, and it hurts like a mother!