I've had the Air for a couple of weeks now, and it's been nothing short of excellent. The value that it brings for its price point (MSRP $119) is incredible. I think this is a breakthrough product that will be very popular not only with 360 and VR crowd but also with people new to 360 cameras. I will be posting tests and demo videos in the next few days.
In the meantime, if you missed out, according to Insta360, the Air will be available from Amazon in March. Besides being the official distributor, Amazon is a great place to get the Air because they almost always deliver on time, and very quickly. And if for whatever reason you are not satisfied, they have a very good return policy.
If you're not willing to wait, Pepe Vazquez found these resellers on Aliexpress (thanks Pepe!). But besides the higher price, I have no idea about the sellers' reliability, or how long it will take them to ship to you. And if you ever want to return, chances are, they'll ask you to pay for return shipping.