Ive been thinking about that too,it gives nice 60 damage + 200 hp and damage reduction,could be a good first buy,ninja tabi + shojin and the enemy adc is now doing 50 damage per auto,could even be helpful when ganked,if it blocks even a 100 damage coupled with + 200 hp and bone plating for good measure and you have a pretty good chance to survive.
If not then going for it as a 3rd or 4th item could help with not getting blown up,i think it could work on more aggressive,shorter range adcs like
especially Draven and Luc cause they don't need AS that much so they can stack damage to get even more out of the item
Also note,for the passive effect to take place,you need to be in range of 3 enemies then auto to get the effect,which sounds only viable for melees,but if you think about it if you manage to get the proc you probably don't need to stay in range of all 3 enemies for it to continue to work,you just Dash/Flash run away and you get that active if someone tries to dive you.
Im not sure how big the range is on the item that detects enemies,but it could very well be enough to encompass their frontline,which is very often 2 enemies,which then gives more safety if someone tries to dive you,you get the proc while only trying to survive one enemy