Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A knife can work better

I am reasonable adept with cutting mangoes and have found this particular device not as easy to use. Since mangoes have a pit that are wide from on one axis and shallow from the perpendicular axis, lining this up is really important. Many mangoes do not lend themselves easily to figuring out which axis is flat and which is shallow.A knife works much better for me.