Triathletes are more likely than most cyclists to use wrist computers over bike computers.
(Cue joke about triathletes not being serious about cycling.)
Fair enough, but they are not really cycling for 45 hours :)
If anything triathletes are least serious about swimming
If biking around 5000 km yearly is serious enough then I'm one - using only my phone to track. Since I will be taking my phone with me anyway, I don't need another device.