I gave it an 8 because it pretty much just means your two weapon fighter gets a bunch more AC for very little input. Get a shield of bashing and you're even doing 1d8 with the offhand, that's not bad at all. If you're going two weapon style anyway, there's almost no reason not to take this. And paladins... holee sheeit. Divine Shield anyone? By mid levels, you could easily have a shield with +7 enhancement to AC and has a +7 enhancement bonus to attack and damage. That's not bad. By high levels this could be as high as +12 to both. No other ability can give you a +12 enhancement bonus to either armor or attack... this gives you both.
So... combine the two with shield expert and get the best of both worlds.
-The Souljourner