SimulationCraft alows you to input your characters gear and spec and simulates thousands of scenarios in order to p[rovide you with an idea on what stats you should be looking for on potential upgrades.
If you want to have your character Simm'd to generate some stat weights that you can put into addons like Pawn, make your request here! Me or some other generous individual will sim your character and get the information to you. This will make it a lot easier for you to determine what gear is actually an upgrade for you, and cut down on the decision time during raids :)
If you do make a request PLEASE use the format posted below in order to make it as quick and easy for the person doing the sim as possible.