RE: Replacing a 105L Hyper
I read all the replies on the "Ask the Team" forum under the same heading.
An excellent discussion for sure. And very valuable information for you.
I think Geoff's point about sailing in fresh water may be the most critical issue.
Although you are tall, you are quite light in weight, which on your fresh water lakes is a good thing, but some of the others (Steve C. is also fairly small but sails mostly salt water on the west coast I think, and Ian Fox is a very big guy, and sails on salt water in Australia), may not have the Isonic 101/ freshwater/less steady winds experience.
So, I think your decision to go for the Isonic 101 is probably the best, and I'm not sure you would get significantly better speed with the Is94.
The speed potential on any of these boards is going to be both sail and fin related, and tuning to get the most speed from the drive in the rig, and the least resistance from the fin.
I am quite sure you are going to get significantly more speed oriented TOW on the Isonic 101 in your freshwater, fluky wind conditions, and more TOW usually means a better comfort level, and along with better comfort you normally can expect better speeds.
Hope this all works out well.