Shaman Itemization and Beneficial Stats

[Shockblock]

I am currently in a guild that is clearing Ulduar weekly, and progressing through various hard modes. I noticed over time that many of the non-tier mail items that drop in Ulduar are statted heavily with armor penetration. As enhancement I also realize that a good bit of my dmg is derives from spells. Typically I have avoided pieces with high amounts of armor penetration even after its buff while i would rather get something that offers crit or hit. I was wondering if I am wrong in approaching Armor Pen. the way I have, is it something I should try to get? I mean my top two damaging abilities are typically Melee/Windfury respectively. Please help me out I am open to any suggestions that may potentially boost my dps. =-)

Current Stats Unbuffed: 4202 AP, 369 Hit, 26/26 Exp, 30.53% Crit, 300 Haste, 43 Armor Pen.

[autobahn1212]

I like to run with a little or more crit then that , you can try simming it using enhsim and rawr. I don't have the links but you can look for any post by levva ( the links are in his signs)