Post by Uiselveti
Do yourself a favor & learn to use this
You will find everything you need to answer most questions like this yourself.
Post by Zxian
Your build is wrong.
As it has been said not 1, but a trizillion times 51/18/2 is better than 51/13/7.
In all honesty, the difference is not as big as people make it seem. Furthermore, the 51/18/2 build is better for well geared rogues (245+) due to the fact that you have sufficient energy regen to do without 5/5 RS. Even with the gear that I have now, the spreadsheet says there's only a 100DPS difference between the two builds.
As for your question about expertise, I'd wager a guess that you should actually pick up the T8.5 helm and stick with the old chest for the 2pc bonus. Armor Penetration is a really lackluster stat for Mutilate, and both the head and chest for T8.5 are very well itemized. If anything, the 232 chest is a straight downgrade in itself.
Furthermore, your gemming seems to be a bit of a mix-match of everything. General rule of thumb - One nightmare tear
somewhere in a blue socket (the one that gives the most AP or Agi), 40AP
in red sockets, and 20AP/10haste
in yellow sockets. 20AP/10haste
are both beneficial depending on how much hit you already have, but neither is a bad choice.
Also, for the love of all that is holy, put Berserking
on both your weapons now
. Like.. right now. Buy the mats, find an enchanter, and get it done. At this stage in the game, 50AP just doesn't cut it.
Like Uiselveti said, learn to use a spreadsheet. It will help you understand the value of the different stats on gear, as well as help you decide what are proper enchanting and gemming choices.