The Sun Sombrero looks good. How does the brim of that hat stand up in a strong wind?
For kayaking the best hat that I have found is the REI paddler’s hat . The brim usually stands up to a good wind. Only negatives are that the back of the hat can touch a PFD or backpack, and the chin strap needs to be replaced by a cord lock. 
That said, once the wind gets up to 25 or 30 mph and above, a large brim is a liability (unless you like to look like that guy on “F-troop”). On one very gusty day in the Everglades, I felt like the “flying nun” (felt like I could turn my kayak by merely shifting my head) and I switched to a buff pulled over my neck and around the back of a baseball cap.
I also have the Sun Runner, and it’s main asset to me is that it is very stable in the wind, and can be converted to a regular baseball cap. However it offers very little ventilation when closed and is much hotter in the Florida heat and humidity, for me, that a brimmed hat. When there is very little breeze it feels like my head is baking in an oven. YMMV.
Greg Stamer