do these have the same memory optimisations.

vectors.as

//create dynamic vector and fix
private var _items:Vector.<uint> = new <uint>[];
_items.push(1);
_items.push(2);
_items.push(3);
_items.push(4);
_items.push(5);
_items.fixed = true;

//create static vector
private var _items:Vector.<uint> = new Vector.<uint>(5,true);
_items[0]=1;
_items[1]=2;
_items[2]=3;
_items[3]=4;
_items[4]=5;