As the OP, I'm going to clarify:
I liked Karoin's English voice, although I don't like Kaorin herself. She's a rather unsavory person (in the anime anyway, she's pretty cool in the manga).
I liked Kagura's Japanese voice better, it had this sweet raspy sound to it. Gave her more character.
Tomo and Osaka, please pardon me saying so, sounded better to me in English than in Japanese. Tomo was a tad too high pitched in Japanese for me to like that voice. It took awhile for Osaka's voice actor to fit her in with her voice. Maybe around episode 5 is when it started sounding natural.
The rest are toss-ups, although I liked the heavy breathing thing going on with Kimura in the English dub.