As Slingbag you realize the weight so then but rather because I would take so much. The way to get to his objective, without removing the backpack is really great. So far everything was great - worn as a classic backpack you realize the other hand even in a long day trip is not much!
The only thing that I would like to see even more, would be a cross belt across your chest, so that the adapter slip under any circumstances and can not be quite as fast snatched by thieves. That justifies not make deductions.
From me strong buy recommendation!