Another observation regarding the iS 111, the fins and the foot strap set up. In my opinion, the 111 is specifically designed for downwind slalom, that's where it excells and is the most comfortable. Beam reaching or working upwind is not as comfortable with the foot strap set up, plus there is a lot of pressure on the back foot, which increases the likelyhood of spin out if you are not fully powered.
This is a big reason I am not happy with the Drake fins, they are not designed for much lift / power, which is not my sailing style. I mostly just freeride on my board and only race slalom a couple times a year.