Originally Posted by
Rahdik
277 Rib Spreader + 277 Lungbreaker should be the best option. Most often times it is. Unless you have a funky gear setup those two weapons should be BiS.
However in ToC it was found that heroic Steel Bladebreaker (the 1.4) was better than Twin Spike + heroic Steel Bladebreaker. The same should hold true for ICC gear. If Rib Spread is 264 and you have 2 277 Lungbreaker, dual Lungbreaker should be better. If they are both 277, using them should be the best option.
Link me your armory and I will put your stuff in Aldriana's spreadsheet to see what comes out. It wont hurt to consult another source.