Review (4/5): It's big
I imagined that all toiletries bags were about the same size, but I was wrong. This one is, to my way of thinking, too big for travel. That said, it's probably great for keeping normal-sized containers organized in an apartment setting where you're sharing a bathroom with housemates. Like all Gonex products I've tried, it's well-made with even stitching and fine attention to detail.
There are four gusseted pockets in the main section, three large ones and one small one for, say, a toothbrush or a razor. Each of the two main sections has a full-width zipper pocket at the back, but they're probably best thought of as either/or. Either you put stuff loose into the big pockets or you organize your items into the smaller pockets in front of the big pockets. I think it would be difficult to use the smaller pockets if the big pockets were full.
The third section is clear and more tightly sealed than the other two sections. I doubt that it's waterproof, but it's dense.