RE: iSonic Questions
I will answer this as I have both an iSonic 125 and a Carve 122.
I am a little lighter at 72 kg, but tacking is no problem on the iSonic 125. I was worried about it at first with the short nose, but was suprised it was fine. It does require good technique, but I found that sailing the iSonic a few times my technique adapted just fine. You can step in front of the mast, the key is to do it quickly with light feet...
I have sailed it with 6.6, 7.3, 8.5, all three of those were good. I taking .5-1.0 m2 off each end of the Starboard recommended range gives a good sweet spot.
The Carve 122 needs *a lot* more wind. I find board width to be a more accurate way to measure a board, versus volume. The Carve 122 is 68.5 cm wide, more comparable to an iSonic 115/111, the iSonic 125 is 75 cm wide. I also find uphauling much easier on the iSonic 125, despite the similar volume. The Carve 122 sweet spot is more 5.5-7.0.
If you are worried about getting back when the wind dies, the iSonic schlogs better, and goes upwind better while schlogging, probably due to greater width and boxier rails.
(Roger: Please see my additional questions above.)