when playing Ezreal when in doubt.
 

Build blood thirsters had three last game ended game with 281 cs and 512 ad.

But then you wouldn't be able to have either Mercurial, Last Whisper, and IE/Trinity. Not worth it IMO, as those would make him do more damage through his autos than 3 BTs would.
If you're playing Talon/Riven/Kha/Mantheon though, go for it, BT stacking on AD casters/assassins is amazing.

i had last whisper and sheen as well as the berserker greives

almost had trinity but we ended it before i could back
ended with 16k gold

dont build trin force on ezreal now, icebourne gauntlet does its job much better

don't need anything but bloodthirsters