Dual Coil is fine if set into TC mode properly, so I'll address some things to keep in mind.
1) The Samsung 30Q yes is safely rated at 15amp Continuous Discharge (CDR) but can be wiggled up to 20amp CDR (this will however decrease their life as it puts undo stress on them), with a Pulse Discharge of about 30amps (but again this puts even more stress on the batteries and decreases their life span even further).
2) If you are asking about the relation of Ohm's Law with the Cuboid and whether the resistance plays a relation, yes in a sense it does, Ohm's Law is more for those on mechanicals Voltage/Resistance=Amps, resistance plays only a factor on a regulated mod to tell the mod if it can fire a coil or not, regulated mods use Watts Law (Watts/Lowest Battery Charge=Amps). Using that formula, we can reverse it, remembering that the Cuboid is a series battery configuration, mod regulated mods shut down at about 3.2 to 3.6v per cell (low battery warning), we'll use 3.2v, in a series that voltage is doubled, so max watts the 30Q in a series can handle using this formula 6.4vX15amps=96Watts.
3) Temp Control mode you could possibly get away with 100watts as power cap, then adjust your temperature to taste, once the TC cap is reached, the mod pulses the voltage signal to maintain temp, so only time you are full power setting is initial heat up, after that the mod will pulse for example between 20 up to 100watts with a median discharge of power in the 50 to 60watts range which won't overstress the batteries.
Nice mod, nice batteries, sounds like a good setup. If you are worried about the battery safety, the 30Q is safe in the ranges I've posted, Link in my Signature Line goes to a blog I've done that breaks down where batteries are safest at what wattage ranges, and links to authentic battery vendors. Other battery models you might look at, to keep the 3000mah the 30Q has, the LG HG2 (chocolate brown) is similar but has a 20amp CDR, another 5amps the 30Q does not, the Samsung 25R is a workhorse, only 2500mah and 20amp rated though it is more forgiving up to 25amps, the Sony VTC4 is only 2100mah 20amp CDR rated though it can handle 30amp CDR with only a decrease of battery life but do it safely, the LG HE2/HE4 are similar to the 25R in ratings. So you have other options out there, but the 30Q yes is safe in TC mode with 28awg Nickel in a dual coil configuration if you are not going crazy with it.