I agree the concern over the old F-Type but new 150 is really a different machine.
iS150 has a squarer outline, and is super thin with contour deck compared to older F-Types, giving a much more direct and hi speed control ride. Unlike FT's, the new 144 and 150 both are built specifically around DFC which significantly alters ride style and allows these boards to run fast and free at speed.
Basically 150 is the optimum "big boys" lightwind design IF you ignor the 85cm PWA rule.
(in other words, the 144 is compromised in practical design by 85cm rule limit: if that did not exist, the ideal "big boys" lightwind slalom would be wider)
At the bottom end of your range the 150 can still present some advantages... But, as you get closer to the 16kts end, then obviously this wind strength could be much smaller slalom board territory so the 144 (or 133) would be fine. If you're using an active pumping style to get going, the narrower 144 will be less of a limitation in the light wind, but provide a "narrower" feeling ride (and turn) if that appeals to your style.
Futura 155 could be loosely considered an option, but not really in the same ultimate efficency (board size vs planing) as the iSonics in this case.
Greetz ~ Ian
Last edited by Ian Fox; 7th November 2007 at 12:58 PM.