6.92% total spread for all warlock specs... thats 30,167 dps to 28,077 dps
6.20% spread from Aff/DL to Destro.
Warlocks ranked 5 (Aff/DL), 6 Aff/SB), 10 (Destro), and 13 (Demo) out of 31 simulated specs ranging from 31,581 dps to 23,097 dps.
The last 2 specs shown are Discipline Smite and Holy Smite, which are healer specs with significant dps and ranked 32 and 33 respectively.
Like I said, as far as warlocks go, play what you are GOOD at. 8D