The problem with this bag, is
1 not easy to install. I had to have the bicycle shop do it.
2 sits up too high so that it's impossible to mount a headlight on the handlebars
It does hold a lot of stuff. I did a five day self supported ride with this bag, and did not need front panniers.
The bag is nice, but a bear to install. It completely blocks the handlebar visibility so it's impossible to mount a headlight above it. Not good, if you get caught riding in the dark.