Hi AR foils are not great at drifting in anything but the largest sizes, but that is true for all foils that the bigger they are the better they drift. That is because the bigger kites are more rigid, have more inertia, ( more hot air effect
), etc. The high AR foils are excellent at going upwind and are imho the best kites for wave riding upwind, strange
? No foils are particularly excellent at turning, especially the high AR ones, you can helicopter them but that's about it. From what you say you want to wave ride and ride downwind, the sonic or the speed is not really the kite I think for you. They will both be great kites just not best suited to that. If you wanted to instead do a lot of jumping and ride upwind, including on waves, well then you could be looking at the right kites. Otherwise I would consider a strutless inflatable or a more mid AR foil like Pulsion or A15. You are welcome to recast the mold and ride a race kite in waves though
they are certainly fun , especially if you can handle a challenge.