Got the white and green option of this in November, having never worn a bucket-style hat for running, and straight away I noticed my whole head and neck being cooler than when wearing a visor in the past. The inner head band didn't look/feel as absorbent as I thought it was going to be, but I've had no issues with sweat on the face.
I recently wore for a triathlon with a 10k run in full sun, and it was fantastic - very comfy and didn't feel like it would fly off at any time at 3:45 pace. It also didn't feel like it was slowing me down at all, and kept my face/neck really cool, and I had my best run time for that course. And there was another bloke with the same hat!
The cinching cord is easy to adjust, although on more windy days with the wide brim it does still feel like it wants to lift off. And ventilation is pretty good, and I think it could be even better with a thinner side-wall material and/or more perforations.
Now that summer is finally here, do yourself a favour, get one of these, and embrace the bucket!