tiefelj wrote:I did not realize that the vest would hold such a large lens.
Guess I'll have to visit the POTN Support shop.
Jake
Yes, it does, I have the Safari one (the longer one, I mean, I may be wrong with the name) and you have two HUGE pockets (left/right) that are big enough to hold a 70-200 2.8 and a 100-400, one per side. With a little effort, you can even fit the lenses with the reversed hood installed, but in that case it becomes uncomfortable.
Another deep pocket on the top left shoulder holds easily anything up to the 24-105 or any big flash like the 550 or the 580. Or two smaller lenses (it happened to me with the 15 and the 50 stacked (possibly with something soft in between.
Plus, you have plenty of space for extra batteries, CF and other small stuf, plus of course for us smokers there is space for cigarettes and ligher 
I do not use the back pocket, but that one also is VERY big and can hold a lot of stuff. But then getting seated somewhere becomes a problem
A big white one that sticks in the bottom of your spine doesn't do well to both, the spine and the lens (and if its empty and you fall, ou can always try to fall on your shoulder then roll on your back, avoiding to hit the front pockets full of gear).
Overall, I must say that if you fill the vest with big white lenses it really becomes heavy. But personally I find that the weight is better distributed than with a shoulder bag, plus you have your hands free for taking pictures and at the same time, for safety reasons, just because you have all your gear ON you instead of WITH you. Once weared, you cannot forget it anywhere, and it cand be stolen easily. In certain circumstances, that is a great plus.