Can't say enough about packing cubes.  My most complicated trip was a sea to summit, very cold to very hot, trip for two weeks. These packing cubes were indispensable in staying organized (which cuts down on wasted time and aggravation when traveling, I very quickly learned). Also, because they each have a handle on the top, I  used one of them as a temporary tote to take along extra layers on the train to summit.

Based on their construction, it seems like they will last me the long haul.  It's hard to know what confirguration you'll need, so I'm glad I overbought vs underbought.  The ones I don't need I'll give as off the cuff gifts/ gestures to traveling friends.