Yes, it is worth flying business class EZE-GIG: more space, better seats, and improved onboard service, in addition to lounge in airport.
However, I would fly TAM instead of AR, which due to strike currently has many of its flights cancelled or delayed. Many AR passengers are stranded in aiports because of the strike. AR also has a bad reputation for delays.
No doubt TAM is the best option for EZE-GIG.
Rgs,