I drive 53 miles one way 4 days out of the week with 4.56's in the Jeep. Then again, I have a 5.3, 4L60, Atlas and a slew of other goodies spinning 35's. Tach sits right at 2000 rpm at 70mph.
Then again, I'm also a few thousand pounds lighter than a half ton pickup too
JB I believe you'll be happy with the 4.10's. I would advise on looking into those Detroit TruTracs tho. All gear driven limited slip and I'm sure they will be a beast under your truck, especially in the snow.