If you ask me, i will said most of the forum is stable, and you will get your payment for your posting but make sure you don't spamming in the forum, if not none of the stable forum will pay you.

My list would be:
1. MMK (it is not scam, may be you spamming there)
2. Forum herer WMM is the best
3. Diamondtimes (have a good rate, but many are not paid yet)
4. GET (long and old forum)

Other that i havne't join yet is Myhyip and laptopdiscussion which i heard is good too.