At first when I received this pencil sharpener in the mail, I was not quite sure how to use it. I thought that you would just insert your pencil and rotate the handle in order to sharpener a given pencil. Although after some online research I quickly learned that you have to pull the silver piece forward, pinch the two black tabs (making them closer together) and the finally insert your pencil and then remove your fingers from the black tabs after you have done so. I noticed that this pencil sharpener is really quiet, so it could be used in an testing environment in which silence is a requirement. Another great think about this sharpener is that it operates without power and without batteries, I can see where this would be an advantage in some cases where there is no power and batteries are not available due to their cost or because they are just not present at that moment. But I could see this as an disadvantage as well, because in some environments quick sharping is important and people do not want to put in the effort to rotate a handle in order to sharpen their pencil. I do like that their site has replacement parts and accessories if you ever come to the point of needing/wanting them. If you have a thicker pencil/s they might not fight inside this pencil sharpener because it dose not have a function that allows you to change/adjust the pencil size that you are going to insert (in order to sharpen). Overall, this is a good pencil sharpener due to its quietness, energy-less, and replace-ability (of components of it and has accessories that are available for it). Although some things that you should keep in mind before getting it are to make sure that your pencils will fit in this pencil sharpener, you do not mind having to rotate a handle to sharpen your pencil, and really fast sharpening is not something that is required. Also I would like to add that this pencil sharpener, perfectly sharpens you pencil every time (due to its design).