The best one in all cases is XP boost. Here is the reason why:
- XP Boost: You will get 50% bonus exp or 75% bonus exp if you have Green Stamina. This exp bonus will be added to all creatures you kill. So if you hunt in a place like Glooth bandits (2 different creatures) and you make "A" exp/h, at Green Stamina with a boost you will make 2.25xA exp/h and without Green Stamina you would make 1.5xA exp/h.
-Prey Wild card: With this you would get 40% bouns exp on 1 creature of choice. So if you are making "A" exp/h, at green stamina you would make (A/2+(A/2)*1.4)x1.5 or 1.8xA exp/h. Without Green Stamina this would be 1.2xA exp/h. This happens because the appllied bonus will only affect 1 creature and not all creatures in the hunt. The number will get even smaller depending on how many different creatures are in the hunt.
A general equation for this would be: (n-1)x(A/n)+(A/n)*1.4. This will give you the increase in exp in a hunt with "n" different creatures if you add a prey of 40% bonus exp on 1 single creature. This will be the value without Green Stamina. With green stamina you just multiply it all by 1.5.
Conclusion:
XP boost (with Green Stamina - 2hours): 2.25x(Normal Exp)+Normal Exp = 3.25x(Normal Exp) - 1 hour with boost and another without
XP boost (without Green Stamina - 2hours): 1.5x(Normal Exp)+Normal Exp = 2.5x(Normal Exp) - 1 hour with boost and another without
Prey (with Green Stamina - 2 hours): 1.4x1.5x(Normal Exp)x2 = 4.2x(Normal Exp) - hunt with 1 creature only
Prey (without Green Stamina - 2 hours): 1.4x(Normal Exp)x2 = 2.8x(Normal Exp) - hunt with 1 creature only
Prey (with Green Stamina - 2 hours): 1.8x(Normal Exp)x2 = 3.6x(Normal Exp) - in a hunt with 2 different creatures and prey activated on 1
Prey (without Green Stamina - 2 hours): 1.2x(Normal Exp)x2 = 2.4x(Normal Exp) - in a hunt with 2 different creatures and prey activated on 1
The numbers will get smaller when the number of different creatures in the hunt rise. If it is only 1 creature or 2 creatures in the hunt it is worth it to get the wild card.