surprisingly domainapps has worked best for ours, probably due to their allowing any domain name, title or pic, no matter how explicit, and i say surprisingly cuz they use yahoo/bing and not google, so go figure... yahoo/bing is infamous for banning domains for the tiniest reason, and sometimes they offer no reason at all...
namedrive is 2nd, no explicit pics allowed and their xxx templates are restrained but still, you get decent numbers, but there they have problems with your domains if the names are too explicit, what is meant by the domain, any keywords you pick, etc