Here are the Expectations sections from both data sheets.
The chance of survival depends on the extent of the poisoning and how long it took to begin treatment. Esophageal stricture is a possible complication. Death is possible, though unlikely.
For Calcium Hydroxide:
How well a patient does depends on the amount of poison swallowed and how quickly treatment was received. Swallowing this poison can have severe effects on many parts of the body. The faster a patient gets medical help, the better the chance for recovery. Survival past 48 hours usually indicates that recovery will occur. If a chemical burn occurred in the eye, permanent blindness can result.
Damage continues to occur to the esophagus and stomach for several weeks after the poison was swallowed, and death may occur as long as a month later.
Question: Which one sounds safer to you?