I have used many fitness bands like Honor , Fastrack ,etc. But the mi band feels so comfortable as if nothing is there on your hand. It is quite accurate in terms of step counting and the sleep analysis is really good.
Coming to its battery life it has 10 - 11 days of life if it is always connected to the phone while receiving media notifications.
Lastly the build quality of the band is very decent but the inner cavity which holds the device properly comes off after 6 - 7 months of regular use.
Overall, it is a very good product if you are a fitness guy.