The oxidizer chosen is Hydrogen Peroxide instead of liquid Oxygen.
The reason is the huge simplification of the production, handling and storage.
For small and medium launch vehicles is more convenient because it is a liquid at ambient temperature and pressure and as it is not corrosive it reduces the cost of hardware.
Another main advantage is the possibility of coverting Hydrogen Peroxide into a Hypergolic propellant, simplifying the design, operation and firing of the rocket engine.
The location of the coast of Argentina is adequate for both east and south launches, giving the chance of many different orbit angles.