I have a long melon, and had a ProTec TwoFace (they quit making them in '11).
I just got into a Sweet Strutter that fits great.
My wife and girls wear WRSI helmets. If you have an average to large (but not huge) head, look at WRSI. They are very easy to customize to a big range of head sizes.
I think WRSI's are ugly, but knowing the level of R&D that went into making them safe, they're beautiful in their function.
Ultimately, I couldn't agree more with Don's try-it-before-you-buy advice.