Both.
As Corvina, Ayu's is bright and flowery, something that almost anybody could love which is good but there's nothing really to grab you.
Kuu's is very interesting. I love the fact her pics are over the place; not one blends in with the other. The only bad pics are the blonde wig and "elephant poo" (Kuu looks more of a random anime chick than a human being.
)