I think I can help you out with this one:
The first I applied to was CPAempire, ( got in)
Then I applied to Azoogle ( twice) no luck and I couldnt bother to call ( i wasnt seriously about CPA at the time)
I heard about MaxBounty, from a blog
and he recommended MB, I was quite iffy because I read something with Shoe saying they didnt pay. But I signed up and got in same time.
CPAempire : I dont I havent converted anything with them, and all of my keywords in one of my niches were rejected but with MB with the same keywords I had no problem.
I love MB, its pretty simple not as much offers, but I found some that work for me, and just today I $33 from two leads.
Barely in mind it took me 6months and 12,000 impression to make $30 with Google Adsense.
I heartily recommend MaxBounty :thumbup: