The Scott Patrol E1 40L Airbag Backpack Kit is a more voluminous than average fan airbag system pack. While the backpack itself has some nice features, the real appeal of this pack is the Alpride E1 fan airbag system, which is also available from other brands such as Osprey and Black Diamond. The pack itself has some significant flaws, but for certain users looking for a specific set of features, this could be a good fit.
The Mammut Refillable Airbag System Cartridge is a convenient, easy-to-fill, and high-quality option. The challenges in finding refill points depends on your location, and may be difficult to find in Europe, but the standard fitting allows for a higher chance of finding a refill point. Overall, the high-quality build and versatility make this a good option.