Corima CF rims are supposed to have less cracking issues than the Zipps (although the cyclocross Pave version Flyod Landis uses is supposed to have double the impact strength and only weigh 40 grams more per rim). This is only based on what I and others read at weight weenies, etc (so take it with a grain of salt)

Corima does supply the rim for the Campagnolo Bora rim so it is good quality. I have heard that they are available for $255 US each-rim only (less than the $400 each for Zipps). Again this is what I have been told and that price could be BS (I haven't ordered them myself, but thinking about it in the next 6-12 months)

Reynolds is another good CF wheel manufacturer. Their first generation hubs were high quality White Industries hubs. They switched those to something else not too long ago (I'm not sure what they are using now)

On more thing. I'd stay away from the Ritchey Zero system hub. They move the non-drive side inward to equalize the tension, but all this does it reduce lateral ridigity on both sides due neither side having a good bracing angle anymore (check reviews of Ritchey rear wheels to see what I'm talking about)

Good luck.