ok..I've got the 92v2 2017 ,fantastic board goes like a rocket ,I think the v3 2018 is even better ..? they even made a 95 litre slightly wider .
I have used a 5.0 to a 7.0 on mine ,but it has to be blowing well for my weight ,96.5 kgs .but its a keeper ..mine maybe a little hard in chop
but still rides over it ok ..
had close to 36 knots on mine I'm sure it will do more ,sorry can't comment on the smaller isonic ,but i'm sure they would be pretty good too.
heres a vid I made a while ago ...you be the judge ..

26-8 knots of wind