i think the cc sounds best of the three, then the custom, then the c5. the c5 is nice with the middle pup on a strat though. i dont use the c5 split by itself but i think it matches well with the ssl2 in the middle.
Jackson MIA (D!ck) just installed a CC in the bridge of his strat style guitar 2 weeks ago. He's got it split and can use it in conjuction with hotrails. I thought it sounded pretty good. I'll PM his email address to you and you can ask him.