Handy!  Started using these a few years back.  We pack some basics used for driving vacations.  Just grab & go.  They hold a bunch of stuff, are stack able, and just the right size to not overload and make them too heavy.  Latches are quite sturdy, and offer a facility to lock, by using two padlocks.  However, they are getting harder to find.  It'll be a pity when they're no longer available.