User blog comment:Care Level/Itemization Holes/@comment-12314620-20130826183240

Armor pen boots might become a thing on adc:s improving their already godly lategame damage if % penetration would stack normally with LW. About rapier: ability being toggleable and offering (in your initial post) something as strong as % ad increase, would you really think that adc:s wouldn't get it because as slow? I mean how strong would Mf be? how about ashe just focusing to spam already low cd volley as main source of damage? Actually I think I might even get it on Caitlyn after getting fed just to instagib people who happen to be away from their team just using my ult. In my opinion Zed doesn't need any kind of buff in terms of items, I'd go as far as say that no assassin (which is currently played as assassin) needs itemization buff (although the idea of chalice variation for ad players is something I'd love to have). About ad casters I'd just hate to see more Irelias/Renektons/Darius's etc. building glasscannon builds after getting fed in lanes, failing every team fight because they can't reach a target alive (yeah, sometimes people actually know how to peel) and blaming the team although their failed itemization cost them the game.

And diamond sightstone... Well imo too powerful for pretty much any reasonable price. Even if you can't clear the ward you still know it's there, see it's timer and all this for practically free. The power only increases in higher level games and as somebody already mentioned champs with aa reset could clear wards even with 2 second visibility.