Break in period for sure, I hated the Subtank for the first day, tasted foul, yet it vaped like a beast so I cut it some slack. Now I'm glad I did, factory machine oil taste has gone completely and the taste is barely different from the Nautilus, although the Nautilus does have outstanding taste so it is expected. I vape at 25w on the .5 coil, and I'll push it to 30w if I feel like annoying my mother.
You'll also find further sweet spots, such as juice ratios, and nicotine content- which I recommend cutting in half if going from the Nauty to the Sub!
Experiment, and you'll find what your looking for!
