I really like this band - the overall quality is excellent, the design is fun, and personally I find that the buckle feels safer than the original Garmin band's twist-lock closure.
Two things stop it from being absolutely perfect. The first is that the Vivofit 2 doesn't fit as snugly in this band as it did in the authentic Garmin band. I find myself checking it more often and fiddling with it to make sure it is secure. The second is that the positioning of the button on the band doesn't quite match the position of the button on the device, so it is quite awkward to change mode, start/stop, sync, etc.
Overall, a solid, inexpensive band which is good, but not as good as the manufacturers' own.