I've found that "exclusive" content isn't all that important for the initial sale in the long run. Yes, a new site that has new content will sell at a much better conversion, but after a few months it all settles down. I look for sponsors that actually seem to understand the niche they're trying to sell and has a great tour.
Having said that. At the end of the day it doesn't really matter. The surfer wants variety. Some buy the exclusive sites and some buy the cookie cutter sites. Shove every option in their face to try and make some money.
Case in point, I recently added some "OLD" sites (been around for a couple years) into the rotation and made some sales that I wouldn't have otherwise. In fact, now that everyone has jumped on the adult.com reality sites, my 10dollar and adultplatinum sales are slowly going up..
