The vibrams were a disaster.  They were brutal on gravel & steep descents.  Definitely need to see the ground, but you're always walking a lot of easy surfaces that could be run with more padding.  Descents scoop up loads of dirt.  Getting cow manure on your paws is guaranteed.

Then came another human paw failure. It's real junk compared to a lion body.  It started as a metatarsal pain which went away after a day of rest & returned after 10 miles, but wasn't crippling.  The trail run blew it up, despite being less intense.  The same paw malfunction happened in shoes, before.  Suspect it always began with stepping on a rock the wrong way.