So, I'm anticipating buying a full-frame camera next year sometime. Instead of having mediocre glass (or not enough FX glass) before I get it I'm going to prepare. My dilemma is between the Nikon 17-35, Nikon 24-70 and new Sigma 24-70 HSM. The 24-70 lenses really appeal to me because they're basically the perfect range on FX, they're both brilliant quality and I just can't imagine wanting anything else for walking around. The Nikon 24-70, which I have handled (and even put on the D40 and walked around with that! :smile , is a gorgeous lens and it really feels like a tank but I'm worried about its size. D700/24-70 owners, do you feel like it's a burden to carry around everywhere? That's what brings me to the Sigma. From what I've read it's nearly on par with the Nikon, and not only is it less expensive (which isn't a huge issue), but it's about half the size! Its size is the biggest factor for my lust. I'm sure I would get looked down upon by some other Nikon shooters for using a nice Sigma lens on a D700 but when it fits my needs I really don't care. Finally, there's the 17-35. This is the range that makes the most sense for when I'll be using it with the D40. On top of that 17mm is super fun on full frame, and I could just buy a 50/1.4 for the middle (I'll also have a 70-300 VR) and have everything covered. Thoughts? Should I cover the range nice and tight with a 24-70/70-300, and if so, which one? Or should I be a bit more daring and do the 17-35/50/70-300 combo? The 17-35's size isn't as much of an issue as the Nikon 24-70's which is a nice advantage.