They're all UBER pretty.
I listened to the original Automatic (Elize), and they totally PWN her.
I have to say the ones that pops out the most in the labed website picture is Kuroki, Hotaru, and Haruka.
----
EDIT: Their second single is something different. If it's good, I really can't say. But it's different. I like the introducing instruments, if they continued that motif, it definitely would have came up to/ just below par.