I've had it a week now and I think it's great... although it's the first smart watch I've had, so nothing much to compare it against. It's very light, and no bigger than a regular watch - in fact, it's a lot smaller than a lot of male watches you see these days.
I used the navigation app the other day to direct me to a pub in London, and that worked fine.
The battery life is good... the advertised 2 to 3 days is correct.
And I love the notifications. Sitting in meetings I can just glance at the screen rather get my phone out.
Still waiting for the Uber app though