A sacrifice you're making for the added features (like the back and shoulder padding) is that it doesn't save space as much as other options. It folds down to 9 x 8.5 x 2" (23 x 22 x 5 cm), about the size of a folded pair of shorts.
There is no zipper on the top of the bag, which means if you sling it over one shoulder it will gape open. Since there is nothing preventing someone from reaching into the bag, it's less protective from theft.