I have a Lansky Quick Fix, Smith's Two Step, and a Rapala Single-stage fine sharpener. These are all similar to the first one on that page.
The fine ceramic crock sticks in these are set at about 23 degrees. They work OK in a pinch.
I wasn't really happy with the results from any of those, so I bought the Lansky Deluxe Turnbox Crock Stick sharpener set. That is giving me better results.
I am also looking at getting the Lansky Sharpening system to provide more options, especially for our really dull knives.