Hole punch works well up to about 9 pages; too hard to push for the 15 that is advertised. Also if paper longer than 11" standard it is tough to punch evenly as the holes won't be centered on the paper as one side of the punch has a shield to keep 8.5 by 11" straight.
Purchased to make dividers for older 6 X 9 notebook where standard hole pattern dividers don't fit. Used folder stock 2 layers thick. Cut clean holes but with the odd hole spacing it was hard to align the punches to the exact hole pattern. The outside punches can be adjusted with screws to different locations but the punch mechanisms don't align easily and may move slightly when they are tightened again. Granted holes don't need to be that exact but it took several tries (and botched dividers) to get them close to being right.
There were no directions included with the hole punch. While the ability to adjust where the holes are is a plus the screws seem to just adjust the position of the holes not the height of the paper opening. It would be difficult to feed 15 sheets of paper through the narrow opening. I've had issues with holes not being punched in much less than 15 sheets.
What a fantastic hole puncher. It really punches holes well. Best hole puncher I've ever owned. Glad Staples took the time to send me an email asking if I would review this hole puncher because I would be so upset if I wasn't able to.