Don't want to promote JP here, but I also tried the SX106. It is a great board as well although I prefer the ST104 (Wood) for comfort/control in chops. The JP will plane a bit earlier, accelerate in a snap to similar top speed, be a lot more physical but take all your sails. $$ is another good argument, if not the ultimate. Whatever your decision, you will gain in liveliness and speed with respect to your AHD.
PS: don't know the 2007 model exactly but I remember the ST115 felt (and probably was) closer to 108 liters. Don't focus too much on volume but rather on recommended sail/fin range.
Last edited by Farlo; 2nd February 2010 at 06:03 PM.