Charging of Instinct and Battery Status

Hi all,

how long does your Instinct charge? I put mine on USB 3.0 at Laptop with one bar left and it's already have all bars filled in one hour?
I understand that the battery so small is in comparison fenix 3 HR that instead of 3 hours it is already charged in one hour.
On other side it means that Insinct because lack of color display and connectiq uses less juice.
Also I'd like to see when it finished charging because I do not see when it finished. From starting till now I only battery with small wave inside, watch and moving circle.
Or should I wait more and will see if it's charged? Maybe all bars filled is not an indicator?