This bag is awesome!  Has a place for everything and holds so much!  All the pockets and little places to put things is great and the inside compartments are moveable so that you can adjust to different sized lenses and cameras.  I wouldn't trade this for anything!  The straps are adjustable and it's comfortable to wear as well. 

Question: Why is bag fairly  sturdy?
Answer: Has a place for everything and holds so much