Hey,
ShareCash is not just a "middleman" - we do work with Adscend, but we work with many direct advertisers, including ones networks themselves work with, and even some they don't. We have many exclusive campaigns you can't find anywhere else, so don't trust anyone bashing SC because they claim we're just "middlemen." Furthermore, I highly doubt any other PPD site can even come close to the array of offers we have - not to mention our great community and unparalleled feature set. Asking this on a public forum normally won't accomplish much; you'll get people arguing each way. The only way to actually see which will work best for you is to actually try them and see which works best for your traffic and promotional methods.