Diablo 3 is different from other RPGs. Aside from being relatively new; theory crafting is still in the stone age. Choosing gear is probably the most difficult, confusing, frustrating thing in the game, but someone at The Asian Gamer created a Diablo 3 Gear Comparison Calculator updated for the current patch. It takes a while to set up but it supports saved profiles so after you initially set it up it’ll be easier to come back to look for upgrades. I’ve used this so far and it seems to be pretty accurate with gear choices.
Diablo 3 Gear Comparison Calculator
