I originally used to buy another plastic container online, but they so easily discolored , wore and got distorted.  I loved the fact that I could tell what I was eating.  I only washed these by hand, never in the dishwasher.  I also didn't drop them and I transported them in a padded container.
Then I noticed the seal was not that tight.  I mean for they were very airtight.  They all eventually had large hairline cracks, even on some of the lids.  I am not sure what to do with them, since they are no longer able to hold any liquids and they  no longer seal airtight?