A few more points:
-Although it has an amazing sail range it won't be able to cover as much as two boards combo. I replaced one wide early planer + one 95l axxis with it, but lost a bit in the process.
-I wouldn't say that it's best @ 20knots, depending on water state, solid average 20 knots can already become too much. Note Philip said "interesting" which can mean "hanging on for dear life" for a 68kg sailor ;-) I'd say all things considered it's sweet spot is 12-18 (more if flat, and lower for lightweight with a good technique).
-You are a lightweight, do you really need a 150l Go (in all that chop/swell/seawalls/etc)? You could use a hyper as an early planer, and you won't have to worry about slogging.
-raf sail is not the best choice. To use it to the max in light winds, think around 8.5, freerace is good enough (3 cams)
edit: I wouldn't pay more than about 25% for a hyper now (compared to new iS)
Last edited by Screamer; 22nd April 2009 at 08:16 PM.