The downside of the alternative is that you have to be online while using it so they can make sure you're only using 1 instance at a time. Then people get complain-y about that. I think both can work but per-device licenses really should give 2 devices as the absolute minimum. It's too common to have a work+home machine or a laptop+PC etc.
It always feels nitpick-y to me if it's only 1 device.
Although selling additional devices to the same user at a steep discount is pretty good too.