RE: Isonic vs. jp super-x
Agreed - the iSonic will be faster... not ridiculously so though, and much will depend on rider input. Because it is an out and out slalom board some people find id more difficult to find the straps (very far outboard) and keep the board going.
Unless you really want a slalom board - which is really not designed for jumping - there are other options. The Stype is nearly as fast as Isonic, so deserves a go