Some of my personal impressions. I bought a prototype neil pryde 8.5 helium from neil pryde maui last spring .
I raced and generally sailed with it this past summer on my old F-2 lightning race World cup edition ( 249 liters) in everything from 0 to 35 + knots.
More specifically one light airs day, 0 to 7 knots Myself and two others went out to compare longboards .
We all had different 8.5's, which we had time to get our impressions of as well.
The boards were: a new 2009 phantom race, an f-2 lightning world cup edition, and a mistral equipe xr.
The sails were, as follows: on the Phantom a Loft dagger, again I had the helium, and the Equipe 2 had Neil Pryde v-8.
we all weighed approx 200 lbs.
Now the wind died on us, as such we had no time to change rigs on boards, we did have time to try each others setups.
Ideally we should have all had the same boards to compare sails, or to compare boards, all the same rigs .
To that point like most board/ sail tests this was highly subjective and subsequently not exact .
We sailed one following the next, close but the following sailors stayed well to windward to stay in clear air.
we sailed beam to broard reach. While in point mode the phantom really pulled upwind which was a function of its huge rails and daggerbaord.So this point of sail was not good for comparing the sails only.
So i wont this into account.
The helium felt in hand like the lightest sail, followed by the dagger then the v-8 which had the heaviest build.
The helium seemed to have the best pull of the bunch in light conditions. The loft dagger sailor was really impressed by its light wind pull. I agreed and was suprised by how little the dagger seemed to pull in comparison.
The v-8 being the heavist build, seemed heavy in the hands no suprise there.
The helium was very tuneable giving a deep pocket with min outhaul, in comparison the v-8 and dagger were less sensitive to outhaul adjustments, the v-8 being the worst.
The speeds of the board were pretty equal, but the helium pulled a bit head over time. Not a huge difference but noticeable. Now in light airs one has to wonder how much perfomrance say a 20% better pull or lift is going to show up in board speed. It is after all light airs.
Now sailing the helium in heavy airs proved to be difficult. Hevay air one needs cntrol and that is hauling on the outhaul to flatten the draft.
Now with the helium it seemed to take presssure off the cams, But this resulted in a very backhanded sail as the draft moved aft. Max outhaul and the sail was a monster.
The weekend of this reagatta was gale force event( three people were killed 100 kms away the same night when their cabin was thrown into a lake !! I kid you not!!) In some of the over 30 knot gusts, while I could keep the point on, a beam reach lead to monster backwinding and a few high speed crashes. Now while I am no "awnold" the governator swazzeneger, I am 200 lbs and work out all the time. Nonetheless my biceps and forearms died mid second race trying to hold onto this beast.
The v-8 was more high wind orientated, as evidenced by its build and my friend found it overpowered and "tolerable" in the same gusts ( the dagger wasnt used by the phantom sailor this weekend, he wisely used a RS slalom)
Now I used a 460 X-3 mast , no not the top of the line mast BUT it is one of the mast options.
While neil pryde advertises this sail as a tight leeched sail like previous designs years back it isnt as tight leeched as one would think.
Putting this sail beside a mistral IMCO OD sail the leech is every very loose. But not as loose as the v-8 .
those old north prismas ( the original prisma's)and Imco sails still have the tightest leechs around.
find a old big prisma ( good luck) for light air pull and your golden.
Anyways hope this helped
jeff Earnshaw aka shredulato
a few other old sticks.