What were they drinking at last years IOM Worlds!  Cause what ever it was I don't think it's doing them any good.  From my point of view they are set to spoil the good looks of a Yacht with a silly 'Moustache'.  We used to call them Spray Rails but some Frog eating Frenchman thought they looked like a moustache and it's stuck.
I can understand their purpose to provide dynamic lift when the bow buries.  However, realistically how often is that?  As for the majority of the time they provide a very very small percentage of lift but at the greater detriment of forcing the water back onto itself which in effect is trying to push the hull backwards.  Also, when the hull is heeled the rail is digging in causing additional drag but I can't make my mind up whether the curve is pulling or pushing the bow into or out of the wind, either way it's probably not favourable.
As you can guess I don't get it.  If or when I go down a similar route I'd opt for the Diamond shaped bow.  Now doesn't that look both sexy and fast.  It's the difference between a Beetle and Porshe 911

Look how the bow wave stacks up where the moustache hits the waterline.  Where every designer is seeking ways to reduce drag and increase speed surely this is a step backwards?
I've read comments about the above moustache being to high on the bow so of no use.
What have the Spanish done to the classic Lintel
I'd like to see more photo's of this IOM as there's probably benefits from this moustache/ spray rail