I use the Toptank mini with a 0.15 ohm Ni200 Kanger coil. The coil actually reads at 0.21 or .22 ohms (always in that area) in my TC mod. I hit this in TC mode at 470F (245C). The wattage does little in TC mode except bring you up to the temperature more rapidly. I use 38w of power in TC with Ni200 coils and in VW with .5 ohm SSOCC coils. Vape juices vary and a bit of fiddling is required to find the exact right temperature in TC or wattage in VW mode. That's with a 20A 18650 battery. The shouldn't matter a great deal if you have a fully adjustable mod as long as you're over say 15A.