Runners are superior to boots everywhere, not just at Philmont. Seriously.
If you dont believe, hike a few hundred miles of rocks, roots, water in each to make up your mind.
I have hiked some unfriendly terrain. Miles of boulder fields downhill, miles of trail that is filled in with softball sized rocks, wet feet for days, trails that are nothing but roots, steep uphills that require hand over hand climbing, etc. Runners do great in all of it.
You will roll an ankle from time to time in any shoe, especially if you are careless. Boots dont help that at all, they actually may make it worse by reducing feel and making you clumsy with heavy weight on your feet. They are heavy, they tire you out, they make your feet hurt, they dont breathe, they dont dry, and they just might cause blisters.
The only bad thing I can say about trail runners is your socks get dirty quicker due to the mesh, and require washing at least every 2 days or dirt buildup can start to cause foot abrasion. If you walk thru water they will clean themselves though and stay nice and clean.

