I live in Oregon, so more rain, mud and dirt mountains. I have always run in either Kigers or Salomon Sense Rides. I would say it all depends on terrain because I definitely use every bit of traction on my Sense Rides and then use the kigers as more of a road shoe.
I live in the middle of a state park in Ohio and run the trails all the time. Definitely need trail shoes as it's an oddly hilly section of an otherwise flat state. And the weather in Ohio unpredicable. It was 60 and sunny three days ago. Now it's 20 and snowing.