Ohmwrecker: Never ends up being a wise purchase.
Any time I've ever tried going Ohmwrecker, either there aren't enough enemy turrets to use it on, or our team is behind and defensive, meaning you can't dive enemy turrets. Rushing it is too expensive, it gives inferior stats to a Sunfire Cape in most scenarios, and its use is far too situational to be of practical use. And with all the new "kill turret" mechanics flying around, the optimal scenario for Ohmwrecker is almost non-existent.
I'd love it if a Rioter could prove me wrong.