Pryde Helium 8.5M

I am looking for the most powerful sail I can find, the best sail for early planing that is a reasonable size. Can someone who has experience with the Neil Pryde Helium sail please tell me if they are as powerful as Pryde says. Pryde is promoting the sails as having power equal to a sail one square meter larger--for example, Pryde says the 8.5 has the power of a 9.5. Pryde says the 8.5 has a sail range of 7 to 12 knots--which seems very low. (I don't plane with my 9.5 until 12 knots.) Are those numbers realistic or marketing hype?