Although the Golden Starfish is a variable item based on insight and ability, the first time use grants 50,000,000 exp. After that it's a static 5,500,000 exp for level 99 Aislings. For those looking to advance in their Medenian paths, it is suggested to pair this item with other reward items like Andor Chests, Frog Sets or Mother Erbie Gifts. An important thing to consider is that, since GSF are ability based, you should always use static items like chests or quest items before using the starfish.