We're working out what we think - we'll add our view here!
Ortlieb says:
The first waterproof backpack that opens like a travel bag offers a new level of convenience for your outdoor adventures and short trips! Anyone who’s ever faced the task of having to quickly locate a particular item in the depths of a backpack will love the new Atrack!
We're working out what we think about Ortlieb's Atrack 35 Litre Rucksack, we'll add our comments here in due course.