this is hard, definatly.
konota - she would be better as a good friend than an every day person, however i would still love to be by her
kagami - the tsundare, that shit gets annoying, but she is prety balanced, and would be a good choice
miyuki - MOE, yea, all in all a nother good choice, however you would feal a bit guilty about it, thinkign am i takeing advantage of her.
tsukasa - personaly she would be great, a good one to be with 24 7 and very little matnence.
i always thing konota would be best with me, but everyone else is a close second