I see no problems for warlocks in PvP except their class skill cannot be used aggresively. It works if you use it behind cover, then peek and shoot. But it is nothing like hunter dodge, and it also does not offer the strategic value titan barricade offers (best way to get heavy ammo, block entrance). Melee is slower than hunter's, but stronger. Has better granades than hunter. Supers are good. No problem with warlock movement (PC! Don't now how it works with controller). Cannot say much about exotics.