Also not directly related, I've been using comma for 4 years and it's been really fantastic. I feel safe and confident with it, and used it on many long trips. Stop-and-go traffic is no longer bothersome, and long boring drives benefit from the safety of the system.
If you're somewhat car+tech inclined, and have the right car, you should give this a shot.
Yes, I think they ship worldwide and they have various language-speciffic channels in their discord as well. I don't see why you would think it's US only.
Mostly because of the Maps. It's not trivial to have accurate Maps of all the world. Google Maps is, for example, quite less accurate here un Switzerland compared to UK, where I have also seen it.
Given that we're talking about a driver assistance system, I assume the quality of the maps can hugley affect the quality of the system. I may be wrong of course.
If you're somewhat car+tech inclined, and have the right car, you should give this a shot.