While most skins will work in pretty much all terrains, if you are moving through some steeper or longer hills in the backcountry, you’ll want to make sure that the weight, grip, and glide of the skins allow for a wide range of possible movement.
Larger hills are traversed through a series of switchbacks, much like an old-time train traveling up the mountain. Therefore, a skin that allows you to grip and glide in an equal measure is probably the best way to go.