Travelocity or Expedia affiliate program?

Which makes more sense for affiliates: Travelocity/WCT XML or Expedia/IAN XML?
Please share comments on the XML (self-branding), not the normal affiliate linking programs.
I am bothered that Expedia seems to not pay any hotel booking fees. And, I am intrigued by the WCT opti-fees, although I don’t see why it looks like I’d get just 40% on this.
What are your experiences? Ease of building? Tech support/customer service? Conversion rates? Income?

See original post by OrganicHotelMarketing