Elementalist bar none, followed by 330 rit, followed by everyone else.
Even though a 330 rit can farm anything with the same template, Elementalist can be adapted to almost any farm in the game. Not only is it as easy as Load template then farm, they also do the same farms as other classes more efficiently. Even though the farms may require more skill and attention for the elemenalist, the rewards are far more worth it for the time you put in.
330 rits are still good for certain farms, but are not as adaptable as the elementalist. They can also double as rangers for the splinter barrage farms.
55 monks are more for beginners now. Their method of farming was as easy as it gets. 55s that used Spiteful Spirit/Spoil Victor wether it was necro secondary or primary was a step up from the 55. 600s see more farms in duos and hero assists for dungeons these days. As rewarding as those farms are, they do take alot of time to learn and do. Basically monks are more for training how to 330 rit nowadays.
Warriors are more safe mode farmers. They can run UW very easily with VwK, but still not nearly as fast as an elementalist or Rit. They have the advantage of non-enchant protections, but usually must rely on another classes elite for HM farms. Which means they will not do nearly as much damage as the primary class, so their farm times will take as long as a 55s. Warriors cannot rely on melee damage in HM because their DPS wont' cut it, especially with HM AI and regen.
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