Here is my current set-up The World of Warcraft Armory

I'm trying to decide if the t7.5 shoulders or the Pauldrons of Unnatural Death would be better for my set

Pauldrons of Unnatural Death - Item - World of Warcraft

I've had the Paudlrons of Unnatural Death fro a while just got the t7.5 shoulders tonight.

The Pauldrons get me to the Expertise soft cap, also they give me more Parry but I lose shield block

The t7.5 shoulders I get more Health, Dodge, and Block but I lose parry and am sitting just under the expertise soft cap.

There is still other gear I can upgrade unfortunately all of the upgrades I still need/want have never dropped for our guild in 25 man Naxx yet.

Any suggestions or advice would be of much help