I think that webmastermoney is the best forum so far.
MMK is also very good and very reputed forum but right now it is not so stable and the payments are delayed causing anxiety in the minds of members. If MMk is back to its original working it is also equally good.
Diamondtimes is also good but it has to earn reputation by honestly paying and another problem is that the rules are unnecessarily strict sometimes. Let us see if diamondtimes can reach to the reputation of webmastermoney.