I'f played both a lot (Dervish being the last one) and I liked the Dervish the best. In my experience more damage (i've never seen soo many yellow numbers flying arround my screen (except AoE-skills)), better defense (warrior isn't good at hp degen vs dervis mystic regeneration), and above all: more energy and 4pips regen, instead of 2.
I would say the Dervish is more versatile, capable of dealing huge damage with one build (not using attack skills), but still able to tank with another build.
Also the vampiric/zealous weapons are a pro on the Dervish, since you can hit up to 3 targets in one normal attack.
And last and least: I like the armor better

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Only pro for the warrior are the more beautiful weapons.