RE: More iSonic Questions...
Sorry, but I have no experience on the Isonic 122.
I sailed the Isonic 115 alot last year, and the Isonic 105 one day in Worthington, Mn.
I've sailed the new Isonic 145 and 101 as much as possible this year.
I'd suggest going with the Isonic 122 and the 8.5 m2 rig. I don't think that going larger (even though it's within the recommended range) with the 9.0 is going to give you a real big gain in early planing.
I found the Isonic 115 to be fairly early planing last year, but I think the "sweet spot was in the 6.5 m2- 7.5 m2 range.
I've sailed the Isonic 105 with the 6.6 m2 Hucker and a 6.5 Retro and it's pretty awesome.
I suspect that the Isonic 122 (at 75 cm wide) will get going pretty early.
Just take it off the wind and pump/ooch a little and it will take off.
Hope this helps,