Hey! I'm planning to buy a new zoom lens for a 6D and I'd like to know what people from macrumors think about it too. Since I'll upgrade to a FF camera, I won't be able to use my EF-S zoom anymore (17-55). I don't usually use the 17mm end (most pictures go from 20~24 to 55mm). I have never missed a wider end, but I really miss more telephoto capabilities. In FF terms, I have a 27-88mm lens (1.6x crop factor), so the 24-70L is out of the question. 24-105L, in the other hand, is only 17mm longer (but 3mm wider), while the 28-300 is more than 200mm longer, but the wide angle capabilities would remain unchanged, so I don't know if those 17mm will be enough or not. I know the 300mm end of the 28-300 is way more than what I need, and I don't know if I'd use it further than 170mm or so. The 28-300mm is also a bit faster at the widest end (f/3.5 vs f/4) but a bit slower at the mid end (f/4.5 vs f/4), and it's also heavier, bigger and more expensive. Another option would be a 24-105L + a 70-200L, but I'd loose the versatility of a single lens. I already have a 200mm f/4 prime (Nikon to EOS adapted) and I don't use it all that much, mostly because when I've needed a longer focal length I haven't had time to change lens. I also have a 100mm 2.8 Macro (and I use it a lot), a 50mm 1.4 Sigma that I'll use after the repair, and a lot of old Nikon lenses (200mm f/4, 55mm f/2.8 macro, 50mm f/1.8, 35-135mm, 28mm f/2.8 and two Nikon teleconveters (1.6x and 2.0x). What do you think?