Bag seems pretty well made. Haven't water tested it yet but figured i would give you an indicator on how big it is.
I used this bag to stuff a down jacket in it (Millet Expert Down Jacket - Men's).
I first purchased the 3L bag which was to small for this size of a down jacket. 3L would fit a Marmot Zeus Jacket fine.
I returned it and received the 5L bag which just fits the Millet Expert fine.