The Koko Head hike is one of the more crazy activities that I've ever done.
It's nuts that the hike is open to public given that it's quite dangerous. There's a high chance of people cooking themselves up the mountain due to injury or exhaustion and then they'd need to be airlifted off. There's no road access. There's literally a section which has train tracks with a 5 metre drop between the gaps.
According to Strava the record time up the mountain is 8 minutes 32 seconds but I wonder if an elite mountain climber could get it done faster.
I messed up big time and wore my Reef sandals to the hike. They handled the terrain well though but runners would have made things a lot easier.