PvE melee DPS? Rogue or Warrior.
PvP melee DPS? Basically anything is good/alright with the right talents, including Ret.
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Ret is literally one of the very worst raid DPS specs, don't exaggerate. Top 5? Out of the 27 available specs, with 20 of them being DPS specs, Ret is not even top 15 outside of Naxx with very specific gear.