It is both a relatively cool straw hat and a good wet weather hat for keeping the rain off my glasses. Its chief distinction from a traditional straw hat is that a traditional hat will be ruined in the rain. By way of contrast, on a particularly hot day I run the Riverz Delta under cold water and let the susequent evaporation enhance the cooling properties of the hat.
I have had the hat badly crushed and folded when one of my daughter's friends sat on it for several hours in the back seat of our car. A light application of steam -- not too much lest the polypropylene melt -- allowed me to reshape it perfectly. Under more normal conditions this flexible hat recovers immediately and without attention from crushing, for example from someone's siting on it or from a short trip in a tote bag.
Securing the drawstring at the back of the head, in the fashion of state police trooper hats, secures the Riverz has quite well in most windy conditions. For stronger winds it can be secured under the chin. The loop at the back of the band works well for keeping the drawstring out of the way when not needed.
Suggestion for improvement: I would like to see Riverz bring back their Optimo model so that I could have a truly packable/rollable hat with the other great qualities of the Delta.