JonAustin said:
Seems like a lot of lens swaps, unless you're also taking multiple bodies.
For travel, I would probably replace the 16-35 and 24-70 with the 24-105 (presuming you have one) and leave the 300 at home.
I wouldn't (at least as far as the wide/standard zooms are concerned). If you've made the decision to bring five lenses, I presume you know what you're doing, where you're going, and how you plan on using them. I never understand why people complain about changing lenses. That's the whole point of having a camera system like this. Sure, the 24-105 is good, but the 24-70 is great (in my experience) and so is the new 16-35 (according to most reviews). With the overlap between the standard and the ultrawide, I'm sure you can gauge which is more appropriate for the situation and manage accordingly, even if you only have one body.
As for the 300, it all depends on where you're going and what you're photographing, which we don't know. I'd love to hear your thoughts on it, because I don't hear about it much and I'm curious for real-world opinions. It seems like a nice budget telephoto option for those of us who won't ever buy a great white.