Includes 2 10 rd magazines that fit flush with grips of the full size CZ 75 and SP-01 models. The Kadet conversion kit will work on the CZ 75 compact models including the P-01, P-06, PCR, and RAMI, but note that the full size magazines will extend below the bottom of the compact grips of these models. The Kadet conversion will not work on the 97, 75 TS, or P-07 Duty models
The above is from the CZ site.
The advantage is that you get a reliable .22 pistol with the same ergonomics and trigger as your centerfire pistol, which is a lot if you're sharpening your shooting skills for defense purposes.
The price is not that high (~350ish) for the quality, but it's your decision. I find a lot of .22 semiautos to be less than reliable or else they are a lot different than your CFs if your goal is training