We have tried several reusable swim diapers and found these to work best for our daughter.  The adjustable waist/legs makes it more comfortable for her (no red marks from tight elastic) and overall construction is  nice.  This is our 4th purchase of a bummi swimmi and isn't our last.  I've only purchased more sot hat we have 2 in each size as she has grown (so she doesn't have to wear a wet or dirty one if returning to the pool or beach quickly).  They wash well (we use Dreft and dry on regular).  The velcro is strong so when washing/drying it is important to secure the flaps so that other clothes don't get caught up in the velcro.  The diapers have successfully held in BM's (though we have changed her relatively quickly after discovering them.  Sizing seems spot on from the company recommendations.