I'm at chapter 17, and these bombs hurt A LOT. Sure he wont be in your party 100% of your journey to chapter 30, but he will definitely make it much easier.
Zafitte is really good for dungeon, Eileen i better for hunting and metal zone, but zafitte is really good after that, levitation, bomb disarm, poison, panacea, etc
Zafitte is a very good utility character. one of only two bomb users which is nice for metal alone. Has frequency amp panacea levitate. That alone is a pretty nice haul.
Seconding Boser's post - She is a great utility character if you've got her levelled up starting with Bomb Disarm and Team Levitation. Her second job only grants poison skills, but her third job grants the ever great Panacea and Giga Regen skills.
The second Job does leave a lot to be desired, but the rest of her utility is so stacked that she over performs in the 6th slot of any team. She competes with Gatz for being one of the best supports in the game. Levitation and Panacea are invaluable skills. Frequency Amp is just the cherry on top
