Used it 40 years ago to build a Flying Dutchman for the Olympics. Tends to be expensive as it is mostly for the aeroplane crowd.  Dyvinicell, Corecell or any of the PVC closed cell foams are standard.  H80 is usually cheapest.   Styrofoam is fine, but check how much it compresses under vacuum.  Can also use PET foam which is recyclable.  For small areas that will be bent, no foam required.  If infusing, get it perforated and scored, or spend an hour doing it yourself.  

RC shunting is pretty easy.  Steering and sheet should be 360 capable (there are other options, but start easy) and fairly fast.  Maybe add an easily visible rudder indicator to the model so you can see where the rudders are pointing.