Don Haines gets the prize! For full-frame lightweight hiking kit, the 24-70mm f/4 IS has some appeal, due to the lighter weight and the semi-macro capacity, plus the IS makes it more convenient to take a reasonable-light shot because one doesn't have to deploy the tripod. I have been pack-hiking with a Cotton Carrier vest, backpack with usual camping gear-water-food, tripod lashed to the pack, and a Canon 60D with EF-S 15-85mm f/variable IS instantly accessible on the vest. 95% of non-wildlife shots can be handled with this single lens on an APS-C camera, and the true macro shots can be handled by the EF-S 60mm f/2.8 I carry in an accessible pocket. I have recently obtained a 6D, and am figuring out what FF lens kit I need. I suspect that I will end up with a day-hike kit containing primes, and a camping-hike kit containing a 24-70mm lens yet to be purchased, my current EF 70-200mm f/4 IS, and 1.4x TC and extension ring.