I didn't know Aegis or Ochain were requirements to play as PLD. Perhaps the "average players" such as myself who have jobs and families to worry about just don't have time to pour into this game for the "elite" equipment?
It's a nice shield. It blocks a large amount of damage due to it's size. The defense rating reduces this by an additional 14% on top of the standard Size 4 rating, and the added VIT certainly doesnt hurt.
The added bonus is the Shield Defense Bonus, which makes this shine. Reduces damage taken even further.
In theory this is a really nice shield, in practise the block rate is a little depressing from what you're normally used to but that's where your abilities come in.
Conclusion, buy it. Have it around just in case. Can't hurt.
Ochain isn't hard to obtain even for casual players. Look at Square's own statistics for the attainment of Empyreans. Within 1 year, more Empyreans were obtained per weapon than their relic counterpart. Hell even Aegis isn't rare anymore with the changes to Dynamis. Given that, one should figure that the main PLD of the LS should have at least one, if not both, leaving very little room for non Ochain/Aegis to be on PLD.