I've used exercise as a catch all for continuous monitoring of the heart. Point being, to get more utility out of a sensor, you'd have to wear it more with less interruption. 30 days without taking off a device is... Unheard of (and wicked cool!). So comfort will be more appreciated in the long term, I suspect

I've mentioned this in the above reply but I'll repeat here: It is not common to wear watches for more than a few days at a time simply because there are not many whose battery will last that long. The effects of fatigue/pressure point from the sensor bump are less observed but not missing. Majority of consumers wear Apple/Android watches that need to be recharged every day. With 30 days on wrist, I can extrapolate that fatigue will be more pronounced - so I am calling it out.