There is no "Best DPS".... All classes/jobs have their pro's and cons, and there are other factors that play a role too. If people were to say that for example Black Mage is the "best dps" class but put it into the hands of an incapable person, where is that "Best dps" then?
The "best dps" would be the class/job you feel most comfortable with and thats that.

What you probably meant to ask is, which DPS class has the highest dmg numbers and stuff like that is irrelevent if you don't master that class anyway, it's just for epeen purposes...