RE: Replacing a 105L Hyper
In light of your latest post responding to Geoff's input, I thought I might come back for an added post.
In a recent thread, the discussion centered on the iS101, iS94 and iS87 boards, and one of the interesting questions was why the iS94. The principal thrust of the conversation was focused on picking a two board slalom quiver, and Ian Fox highlighted the iS101 and iS87 as the most ideal medium/high wind slalom quiver. However, it was also stressed that if one was thinking of only a single slalom board, the pick would clearly be the iS94, as it could more suitably balance both ends of the intended wind spectrum.
Because your latest comments you indicated that your interests centered on high powered sailing, and not on marginal conditions, I think that the scale more readily favors the iS94. If you were signifiicantly heavier (20-30lbs more), the path would point more obviously towards the iS101.
In answer to the question whether you could plane in 13 knots with the 7.6 and a 38cm fin, I have to side with geo and say yes, particularly because of your lighter weight. I know I can, and as I noted earlier, I'm just a tad heavier than you. In practice, I think that you can probably do it with even a smaller fin, like a 34 or 36. A 38cm fin might be a bit on the large side for a 59cm wide board, yet its viability has a lot to do with the physical and performance characteristics of the fin.
Overall, I hope this input helps you in our decision. Maybe Ian Fox will jump in and offer his thoughts. If available, I've found that he usually has a lot to say about the iSonics.