>>351179824-105 is more versatile, however my uncle has the 24-70 and he swears it's sharper (although not by much). I love my 24-105 though, especially because it has an image stabilizer which makes low light shit much easier. Both are weather sealed to some degree and I've had no issues shooting in the rain or by the ocean.
Here's a 100% crop of a pic of a wolf I took with my 24-105 on Provia 100f.
