Scryers isn't a crit boost anymore. I don't think that lasted very long, since it scaled so much better than the AP boost from Aldor. Now, the scryer's necklace does instant damage with a 40 second internal cooldown. According to the math, they both give about a 9 DPS increase, but many people swear by the Aldor necklace.
But the Aldor shoulder enchants are quite a bit better until T6 content, when they start to even out. If you're just now starting the rep grind, don't put too much time or money into it. The expansion comes out in less than two weeks, and the enchants will be either obsolete, or too expensive to put on every new pair of shoulders you get until level 80.