I love these Lock and Lock reusable containers.  They absolutely never leak!  Even when put in the microwave with water inside them they do not spill or have the lid pop off.  They are very durable and do wel lin the freezer.  Be careful if you drop them coming out of the freezer I cracked the corner of one of the lids when it fell out of the freezer.  Also the plastic does not do well for long times in the microwave.  The bottom of some of my containers has become wrinked due to my husband putting it in the microwave for more than 3 minutes.  Also since they are clear they do become stained...