Klove...
I'm just about where you are & figure that I don't really have enough stats to get a good figure, seems like 1:300 - 1:500 is avg signup ratio from what I see, once there's been enough traffic to each sponsor I think stats will mean a bit more...I say this cuz it's easy to get down when you invest so much time & effort and are not getting returns yet
I also found that stats aside, you can get a couple of signups with a low ratio then nothing for a while...guess I have to stop being a compulsive stat checker !!
I have promoted SunnyDollars from the start & it has been my best sponsor, so definitely give them a try!
I'm just gonna keep pumpin 'em out & see what happens!
Ponygirl