Talk:Black Cleaver/@comment-3486816-20120531021420

Doing a small project on cost-effectiveness and I stumbled across something interesting: while is just as effective as  for armor pen (assuming all three stacks) only up to ~113 armor, you only pay ~61 gold for the armor reduction component versus the ~823 gold you spend on 's percentage armor pen. Since you spend about 13 times as much gold on Last Whisper's armor pen, you need to penetrate 607 armor to make them match up in those terms, making them break even in terms of cost effectiveness only against an enemy with 1517 armor.

...well then. Good thing Last Whisper's cheaper.