I have a Warlock- and love it. Titan has a few 'man I hate that' moments against me in PVP, but in reality- it's not that significant. Both are great, depends on your playing style and what you prefer to do during PVE. Titans can do different roles than Warlocks in the VOG, and their Super is more 'in your face' or 'defensive' which means do you like fighting close up PVE or farther away?