If you choose to purchase, my suggestion would be to go with the Big Summer Chest.
Rewards (5) items.
Based on being level 150....
Summer Poncho has a 30% speed bonus and a 30% xp bonus from jobs, duels, FF's
Summer Pants has a +150 lp bonus
Straw Sandals has a +21% money from jobs and duels.
Shell Necklace gives a +21% increased luck
The chests might also contain a couple other items like the "Your Testament" and "Indian War Paint" that are consumable, dueler based buffs.
Lol.... if you choose to purchase, my suggestion.....
So was just a suggestion.
I use 2 or 3 of the items on a daily basis.
Summer Poncho as part of my travel/speed set.
Shell Necklace for my luck set after setting jobs.
And so on.