Cyclists can be hard for motorists to see, particularly motorists in larger vehicles. British trucker Jay Singh observed this firsthand, having spent decades driving a hauling truck around the UK. Singh himself eventually took up cycling, and "after one too many close shaves while cycling in London [decided] to invent
Yeah, neat that it gives you a heads up too.
Yes, very useful on rural roads and quieter suburban streets. It also works well on trails where e-scooters/e-bikes might ride up behind you without warning (to pass).
But in a city, the radar just goes off constantly, so it’s less useful if you only ride in busy city streets.