I have the FS-10 from HJC, with the slide down sun shade. Its a nice helmet, but its the first full face I've ever ridden, so I don't have much to compare it with.
Its not heavy on my head, and its not real noisy when I ride. I especially like the sun shade feature.
I just noticed, however, that there is a "ac-12 Carbon" version that for some reason I had overlooked before. Hmmm . . . that does look interesting.