RE: Question to Ian and Remi on iSonic 145/155
(Remi is most likely as locked out of our own website as the rest of us, so don't take his non apperance too badly ..)
While your sail size of 9.4m on the iS145 will be OK, an oversize 66cm fin is really overfinning this board; it will be rideable - and will help with actually getting the board to plane earlier in marginal conditions but as soon as you are planing, the 66 fin will really be overpowering the board, and esp with a medium weight rider not such a great or practical combo. Typically think about 58-60cm as being the max practical fin for the iS145.
Yes, you will lose a little bottom end range (obviously) with iS145 but overall you will get back more range in your quiver at your weight/sail and wind range, and if you were confident the FT148 was the one for you, then the bottom end of the iS145 won't be worse.
If you really will be sailing a lot in sub 10 kts or flaky wind, then think about iS155 bit otherwise the 145 will be a better all round choice for your weight/conditions/quiver etc.
Planing thresholds in marginal conditions are really signifcantly influenced by a number of variables outside our control (like rider skill, determination, pumping / water conditions and wind quality at x kts etc etc) . One advantage of iS is that it is a very responsive design to a bit of extra input (work) to get it going; meaning it's a very likely choice to run a slightly smaller board than "ideal" at the bottom end of the range in return for that same ("smaller") board giving back a lot more range at the top end of the range.
Obviously, there will some compromise in either case, it really is about minimising the overall compromise. Make sense ??
Cheers ~ Ian