We have been using these bags for a long time and have been very happy with them.  They are not as big, as I would like...but they get the job done.  I hate the thought of putting dog poop in a bag that isn't biodegradable.  And I am upset to learn that mean bags that claim to be biodegradable are not really.  I was pleased to find these bags.  I will continue to purchase Mutt Mitts, and recommend them to people trying to live a little greener one step at a time.