This was my first tape dispenser of the "gun" type. The instructions that come with it say that when you press down on the plastic shield in front the serrated edge will "pop out" and cut the tape. This is true for other models that have a spring-loaded serrated edge and a metal reinforcement behind the plastic shield. However on this model the serrated edge is fixed in place and the plastic shield snaps off if pressure is placed on it more than a few times. I didn't know what the instructions were talking about until I bought (again from Staples) a more expensive version made by 3M Scotch Tape. Further the metal gate/tongue under the front roller isn't spring-loaded either; with its flattened tip tape regularly gets caught on it. Skip to a higher price point.
The metal piece that keeps the tape pushed against the roller sticks to the tape so strongly that you have to remove the whole roll of tape off of where it is seated to be able to detach it from the metal. The surface area of the metal piece in contact with the tape is 1/4 inch. I'm ready to throw it out. Other tape guns that I have used only have the EDGE of the metal piece (approx.1 mm) against the tape and the tape goes smoothly.