My brother-in-law and I are talking about doing it. He did the Warrior Dash with his wife last year and loved it.
The only aspect of this that has me hesitant is you go through the first mud pit right out of the shoot and then have to run the remainder of the 10 mile event in wet, muddy shoes. That sounds like all sorts of pain, discomfort, and blisters. Maybe I'm just not hard-core enough. We'll see.