Except for first time upgrades, just to add on top of your tip.
Max stats between two separate +10 or +anything Warrior Rings are the same, yes. However, a higher +Modifier yields not just higher base stats, but a better leveling efficiency too. IE, a +0 starts at 600 Atk and maxes at 756, a 26% increase, whereas a +10 starts at 1000 and maxes at 1507, a 50% increase.