RE: Slalom versus long-distance
Right, there are no specific technical design differences that gives some of iSonics fundamentally better long course or short course advantages (top speed vs accel/planing). Basically these boards represent A2's selection for his "large medium small" choices for both
long distance and short course racing. Obviously, very long legged "slalom" racing like the Defi warrants slightly different choices in board/trim/tuning than the short sharp downwind M stop/start style PWA slalom racing. Given the overall range of each of these designs, it might seem a little excessive, but I guess in Antoine's case it's not.
BTW, obviously the 97 is actually a 94 , while the 84 is the 87.
Also the finer choice/s of board/conditions relate very heavily to rider size/weight, style (power vs glide) and tuning. Some guys really like to go at it hard, fully powerd and at the same time loading the board pretty hard (larger boards..) while others in similar conditions take a more delicate approach and run with lower drag combos in similar conditions. Watch the two extremes in action, and the differences are very clear - which is why it's important to factor that in when considering or reviewing the "best" or "ideal" board for a given set of conditions..
Not many guys can put the hammer down (and load the board etc) in such a solid phyisical way as Antoine..
Cheers ~ Ian