We have been using the Voyager Medium Travel bags for about a year. All 4 of our kids have them and they work great for them too. We use them mostly for trips, including flights, driving, camping, and long weekends.
Pros: Fit most items standing up. Our bottles don't have to lay down. The medium has enough space to fit what we need without being a bottomless pit.
Another upside is the hanging hook. This hook is sturdy enough and yet doesn't become unwieldy or in the way when packing up.
We also like the mesh zipper pocket and the mesh front. It keeps items visible and still tucked away.
The medium is a nice size to fit in our suitcases.
Cons: More colors are needed. As there are 6 in our family, we have had to overlap colors. I'd love it if there were a few more or possibly the option to customize a name on the front.
Sometimes, items in the side pockets interfere with the middle pockets.