Unless the wearable is very rounded... Me no likey.
They put uneven pressure on soft flesh. And the corners can thin
As this horrible article
http://news.bmezine.com/2008/01/27/things-you-should-not-do/ that is forever burned into my mind..
I have some triangle-ish shaped plugs, but they're closer to teardrop shape, and the only stress they put on my lobes is at the top, which is stronger. I still don't wear them for too long though, just in case.