I understand that their service is "average": not the best, but not the worst. I only flew business class on a 1 hour trip (Buenos Aires-Cordoba), and their service was very proffessional.
Also about Aerolineas, I found an interesting article in "Diario La Nacion", saying that they have finished negotiations with Boeing and airbus, and are planning to acquire 9 NEW aircraft, from the manfacturers. It stated, that plans were originally to lease planes, but that offers were tooooooo good to resist. An announcement was planned to be made in some days.