I have been resting some bags for what it is called "one-bag" travel. That means, a travel style in which you use a cabin-legal bag or suitcase to travel and live for an indefinite amount of time. These sort of bags should be able to hold clothes for up to a week, plus all the technical equipment you need for working online as you go around. Other features that are appreciated in these sort of bags are the heavy duty shoulder straps, suspension systems and organisational/accessibility pockets.
In my opinion, the travel pack sacrifices some practical features in exchange for a sleek, clean and discrete design. This may work for you depending on your travel style and needs. This bag will shine at business travels, urban trips and when blending in the crowd without looking like a tourist.
The bag sacrifices ability to expand due to its semi-rigid construction, it does not have a suspension system, back ventilation or heavily padded straps which come in handy in long walks under heavy loads and it does not have a waist belt, which is also very useful when the bag becomes heavy. Many of the pockets in this bag are flat which limits their carrying capacity. The main compartments are, however, spacious and should allow you to pack everything you need for 4-7 days plus an extra pair of shoes.
With all that said, the bag simply requires you to adapt your packing style and once you do, you will feel that the need for suspension systems and waist belt disappear. Once packed properly, the bag becomes light enough for walks of up to an hour.
At the airport, the bag has some of the best features I have seen around. The compartment for laptop and electronics in the back panel is accessed without problems (as in many other one bag solutions). The small padded pocket at the top for cellphone/passport/boarding pass is also easily accessible and last but no least, the front compartment for the toiletry bag allows you to access it without having to open the whole bag - this is something missing in all of the bags and I have used and I love this feature very much. This bag should allow you to breeze through security unlike any other.
The dimensions of this bag differ from Ryanair/Easyjet ones. The total volume of the bag is still at carry-on limit, but the bag is deeper than what it is allowed. That said, the bag looks small and compact and should not attract attention at the gate. For maximum discretion, the shoulder straps can be stowed away and the bag can be carried by the handles.
Finally, the this bag is priced slightly cheaper than the famous one-bag solution Tortuga outbreaker, and around the Aer travel pack. It it is significantly cheaper than the Minaal, but it will cost almost twice as much as the Osprey farpoint 40, which is a very popular option for onebaggers. As all these bags are of excellent build quality and offer solid guarantees,but in the case of the Fjallraven, what you are paying for is mainly the sleek, elegant and discrete design.
PD: I had initially purchased a green bag which I then exchanged for a black one. Both look gorgeous, but the black bag looks much more discrete and I have found it not to attract attention at all - which is something valuable.