Not really a checkpoint, but I did once get a save in FF2 just after you fight the Adamantoise. I was poisoned and out of potions or antidones, with one team member down, heading for the exit so I could teleport to the nearest town. I got to the exit then BAM! Second boss fight.
It was at that point I learnt the value of a second save file.
It was at that point I learnt the value of a second save file.