There are three issues that limit the usefulness of this blender.
1) Insufficient motor strength - The instructions state frozen berries can be used. The blender does not have enough motor strength to blend frozen berries. We used blueberries, raspberries, and strawberries explicitly following the recipe procedure. We had to wait for the berries to thaw before the blender could function as expected. 
2) Very hard to properly seat the base to the blender container as indicated by the alignment arrows. I'm 6'3" and two hundred pounds and I struggled to get the arrows to align. My wife couldn't do it at all. So, we used the blender sealed as best we could.
3) The battery when full charged and used once was dead the next day requiring a recharge before the second use. This could be remedied by leaving it plugged in between each use.