I was going to say "there's almost no way you can go wrong with a 3D foamie"... But! This one is depron, meaning it will shatter on the first crash. If you want a foamie you can throw around and use for 3D practice, look for one made from EPP instead.
I would look at a TwistedHobbys foamie if I were you. They are made from EPP and can take some pretty rough handling.
Here are some foamies in the right size range for your batteries:
I have three TwistedHobbys planes myself and I can wholeheartedly recommend them!
As for the power system, I would always go with the system sold/recommended by the vendor of the plane, as they tend to provide the best balance and power.