While technically a Sport kit, this rocket is a high performance beast!  Everything from the parabolic shape of the nose cone to the tail cone seems designed to maximize the attitude you can get out of a C11, D12, or big E12 motor.  The time spent to airfoil the fins and to carve out the tail cone for a perfect fit of the motor retainer (which requires some patience and a sharp hobby knife) is worth it when Sprint XL soars off the launch pad!