I guess it depends on where you use it. on my Baja I have 215/75/r15 hankook mud terrains in the back. they are great in snow, mud, and damp earth, but in dry silt or loose gravel they just dig holes, they also hurl basketball size boulders very effectively as well! fro the dry months I plan on putting on a pair of 215/75 general grabber at2. so I can swap the front with the back depending on the season.
the other bonus with running the same tires on the front as the back is you only need 1 size of spare tire!
if you don't need every inch of ground clearance, the smaller tire will be a lot more gentle on your drivelive