The coils in the nautilus come at 1.6 or 1.8 ohms stock. The airflow control makes for a better taste and more vapor. The tank also holds 5 ml.
I have aerotanks. 2 of them. They work very well. I'm not sure if getting a nautilus would really change anything for me, but they are supposed to be better.
In my experience (I have both tanks) the Aerotank is better. I personally don't like the Nautilus. I don't like the look, I don't like the airflow (Aerotank has more precise control), I don't like the flavor and I don't like the vapor production.
I fell for the hype, and very much regret it...