User blog comment:Rapacious/Rapacious's sexy guide to understanding ranged AD builds/@comment-4199297-20120203142959/@comment-3477331-20120206122225

I'd rather base it on the lane and on scalings. You got some good ad ratios and/or in need of sustain? go Bloodthirster. Else go vamp scepter + infinity edge. Also, if you're losing the game, you probably won't be able to farm up the bloodthirster