Just a quick after trip update. The water filtration system worked out quite well on my hike. Since I didn't know for sure about water availability on my first camp I took 6 liters of water (filled both bags of the Sawyer system and had a platypus bag). It turned out that there was little stagnant water that looked horrible. So I'm glad I didn't had to rely on it. Although that would have been a good test of the system.

With the 6 liters I had plenty of water for the second day as well. At the second camp I filtered 6 liters from a flowing creek with very clear water. A trip report with photos is at my blog.