I've had 4 flip face helmets in the last 8 years: RXT Duo, Nolan N102, Zeus 3000A, Shark Evoline 3.
All have been noisier than a standard open face mainly because they have lumps and bumps for the mechanism that standard helmets don't have. The noise is generated when the wind flows over the edges and bumps. If you put your hand up and deflect the wind in front of the helmet it will get quiet, of course this is pretty much impractical to do so the only thing left is to invest in earplugs.
I prefer the flip style, particularly in the hot climate here and I have to say the Shark has been the best of all the ones I've had but it's still noisy. I've been told the Shoei Multitec is fairly quiet but my offsider at work has both the Shoei and the Shark and he always wears the Shark in preference to the Shoei. The Shoei is also twice the price of the Shark.