HoDough has Bubblebuttbonanza, I only tried them for a little bit, but it's already converting very well for me
http://nats.hodough.com/track/NjIzOjU6Ng/
Naughty America's Assmasterpiece also converts great for me! I even won an xbox360 from them for promoting this very hot site! Sign up here pls
http://www.naughtyamerica.com/index2.php?refcode=360/A/
Hundies has Pigtails&Roundasses and also AssLikeThat
http://www.hundies.com/ps.php?s=HUND&u=freetour&pg=8