Just gonna say it, but have you ever actually done one? I mean shit it's 10 miles...while you're soaked and dirty and doing tons of other physical obstacles, like you said monkey bars or crawling over a wall e.c.t. Go out and run 10 miles right now, after rolling around in a muddy creek, then add all of that shit to your run. I haven't done one...but it certainly doesn't look easy. It would be fun for sure though.
I'd never heard of it (thank you google), it doesn't look easy but it does look fun. I'm not sure if running through smoke is very healthy though.