Fanatic must have got their sums right with Shark bearing in mind results of test mentioned and "fact" that Martin Van Meurs got 38 knots out of one. (He didnt state exactly which one ; assume the 130 ??)
Couple of years ago I hired one in Feurteventura (its all they had left) and sailed it in waves !! It was great; taking into account its size !!! Didnt give impression to me that it was capable of both planing in sub 10 knots and then doing 38 knots !!! Think it might need a fin change to do both ???!!!