This tool seemed interesting in the videos and appeared functional, but in practice it doesn't perform even close to the video demonstration. The tumbler doesn't roll smoothly and meets a lot of resistance. Sharpening anything with this tool requires so much effort and time that you might as well not even bother. Additionally, the axle of the tumbler system appears to be off-center, causing it to wobble and making any effective sharpening nearly impossible. I am very disappointed.

Awesome to get a sharp edge without fidgeting with whetstone, angle tips, etc.. Just click, roll, and sharpen

There was an issue with my order getting shipped out initially. But, the folks at tumbler did a great job of making the situation right.