The wording of the spell reads a suit of armor or shield to get the bonus. So the spell only effects one of the two items correct.
But lets say this. If a cleric were to pray for two magical vestments a day. Could he then cast the spell on both? Or would casting the spell on his shield negate the magical vestment cast on his armor?
As dm for my group im leaning to the you only get one magical vestment effect period. No matter how many you have in your head that day. Its just that OR in the spell description. Maybe its just I had a bad day and I have my evil dm hat on lol.
Thanks for replies.