I've been using the Subtank Mini with the Nickel OCC coils since last week. Got them on my way home from work on a impulse, the day I got the IPV4. Personally, I love 'em. I've been vaping them at 450° & 30 Joules and it's great. I just got my Starre tank today so the Subtank got pulled off the IPV. Now I need another mod for the extra tank, though.Anyone tried the kangertech nickel coil head .015?