The manolo boards are very flat thru the tail, less than 1/2cm tail kick, which planes up quick, and the small tail area means minium drag once planing fast(more surface area creates drag)..
I have a 147 wavetray and a 5ft 6" underground directional, and hands down, the directional is faster, and points much higher upwind, while requiring far less wind. (mostly due to the extra speed you get out it = more apparent wind speed) The wavetray can go pretty fast in control to almost match the speed of the directional if you try, but you go downwind to acheive this!! Just an additional note, my directional has a lot more rocker and tail kick than a Manolo, but for all intents and purposes has the same speed/upwind capability in small-large chop conditions that we get in NZ, but in dead flat water I guess than flat Manolo could have an advantage.