I use nonfat milk and it is only necessary to fill the milk up to the lowest line. Anything else overflows. I would not get the newer one, as I have read poor reports for the Aerocino 3. After you froth your milk, use a spoon to hold back the froth, and pour the heated milk into your coffee cup that has your coffee already poured in it. If you use a syrup have that already poured in your cup as well (before adding the milk). Then spoon the froth on top.
You might look this item up to buy it and decide not to go the expense. FEAR NOT!!
I got this little gadget at Sur La Table for $15:
It is a hand held device and runs with batteries. Heat your milk and then froth it with this little gem!