I guess it'll depend on your traffic as well, but on my bear site, Hot Desert Knights is doing nicely for me, so is NakedSword.

On my Euro Twink site, Randy Blue is picking up the pace.

I tried Butt Machine Boys, but it converted too slowly with my traffic.

I tried William Higgins on my twink site and got nothing. Istan Boys has done a little.

MANcheck Cinema is doing alright with my sites, but I find I have to use movie box cover banners over just plain banners. So, on a leather site, I feature leather movies, on a tattoo man site, I feature movies with tattooed men, etc.

If you give us some ideas about the kinds of gay sites you're running, we can probably make some more specific recommendations.

Cheers,
Dzinerbear