Brant and others, have you had any issues at the airport with the Mindshift 40L and other bags this size? I'd hate to invest in a 600, larger bag, etc and find that they won't let me travel with this bag.

Karsaa (sorry for misspelling your name earlier), what Camera body are you going to use with this lens. After reading Brant's links above I noticed that people's suggestions change slightly if your using a crop sensor camera instead of full frame, makes sense.

I apologize in advance for hijacking your thread, but I'm hesitant to start another thread with almost the same exact title by adding "Version II." I own two bodies, one is a 5D3 and the second is a recently purchased 5DSR. If I use the 5DSR with a 500mm lens for shooting wildlife and have to crop slightly, am I getting roughly the same quality photo as I would get with a non-cropped 600mm lens with my 5D3? In other words does the 5DS R change things due to the extra megapixel count? Is it at all similar to comparing a crop sensor to a full frame sensor? The current price difference on a new 500II and a 600II is $500 US dollars, that is making it harder for me to decide (if it was more like two or three thousand I would certainly choose the 500mm). I prefer the weight and size of the 500, but I prefer the extra reach of the 600. I've also read a little about the 600III, and for my needs there's little value (and out of my budget).