I ran this route from North (Cape Hedo) to South (Cape Kyan). It was a beautiful day (plus an extra 37 minutes :) of running with temperatures in the low 50s to mid-60s (Fahrenheit). There was no rain, but lots of wind!
I used hydration vests packed with nutrition (Hammer Perpetuem, Picky Bars, bananas, and gels) as my primary nutrition. I stopped at convenience stores twice for some rice balls and electrolyte drinks (and a Red Bull around 2am).
This is submitted as a supported route because I did stop at my place of residence around mile 65 to recharge electronics, swap out shoes, and eat a burrito and some orange slices.
Around mile 25 I had to switch my Garmin into UltraTrac mode to minimize battery drainage. As a result, some of the mile splits are off and there was one erroneous sub-6 minute mile, but the total time and location data appear to be accurate. It also caused the total mileage to track slightly higher than the actual route distance of about 100.25.
It was a great experience, and perfect running weather. A great way to explore the beautiful island of Okinawa!