Factors in choosing what battery to use in a regulated mod include the current rating of the model of battery and the wattage that you'll be using.
Since the VooPoo Drag is a
dual battery regulated mod, and you say you
don't vape over 80 watts, then you could use two Samsung 30Q 3000mAh 15A or two Sony VTC6 3000mAh 15A batteries. Each battery is good for 45 watts each; using two is good for 90 watts. You could also use the Lg HG2 3000mAh 20A batteries.
WATTAGE PER SINGLE BATTERY on REGULATED MOD:
(Wattage doubles using 2 batteries; triples using 3)
Up to 45W:
Samsung 18650 30Q, 3000 mah 15 amp CDR
Sony 18650VTC6 3000mAh 15 amp CDR
Up to 60W:
LG 18650HG2 3000mah 20 amp CDR
LG 18650HE4 2500 mah 20 amp CDR
Samsung 18650-25R, 2500 mah 20 amp CDR
Sanyo UR18650NSX, 2500 mah 20 amp CDR
Sony 18650VTC5, 2600 mah 20 amp CDR
Sony 18650VTC4, 2100 mah 23 amp CDR
AW 18650 3000 mah 20 amp CDR
Up to 75W:
LG 18650 HD4 2100 mah 25 amp CDR
LG 18650 HD2 2000 mah 25 amp CDR
Samsung 18650-24S, 2500 mah 25 amp CDR
Sony 18650VTC5A, 2500 mah 25 amp CDR
Up to 90W:
LG18650HB6 1500mah 30 amp CDR
LG18650HB2 1500mAh 30 amp CDR
LG18650HB4 1500mAh 30 amp CDR
Samsung 18650-20S 2000mah 30 amp CDR
* If you were going to attempt to use the full alleged 157 watts of the VooPoo Drag, then I would have recommended two 30A batteries which would be good for up to 180 watts. You don't need 30A batteries in a 150 watt mod if your wattage setting will not exceed 80 watts.
* Note that the higher amp batteries only have 1500 - 2000 mAh capacity, while the lower amp batteries have up to 3000 mAh capacity for the longest use between charge.