I have used mine lashed onto my trailer hitch cargo carrier and it kept the contents dry even through driving rain.  I have used them as seats around the campfire.  I've stood on them while I tied kayaks to the roof rails.  They're a perfect size for the rear seat foot wells in my SUV.  I can put one in each well, inflate an air mattress and these give me a near perfect level surface with my seats folded down so I can sleep in the back.  I have dropped them, knocked them around and even fallen on them and they just have a few scuff marks but are otherwise none the worse for the wear.  I really can't say enough good things about these versatile ActionPackers.