You have another option: the Witness line of guns, which are basically CZs in disguise, come with a slightly larger frame, but interchangeable top-ends, so that a single frame can give you a wide range of different calibers. Including .22. Some of their models are a bit more expensive, but have many NICE features.
I prefer CZs to Witnesses, because of EAA (the importer's) crappy reputation for bad customer service, but the Witness guns themselves (built by Tanfoglio, of Italy), tend to be trouble-free in the 9mm and .40 models, and are quite good. I think the slides for other calibers are probably about the same (or $less) than a Kadet Kit.
Note: CZ-75 refers to a much older version of the CZ. The current models are called CZ-75B, and are arguably a better bet. (Some folks call the older guns "pre-B"s meaning before the "B" model was introduced. The older CZ-75s have great triggers, but can be expensive to find, and there's not as wide a range of sights, etc. for these guns.) You won't go wrong with either, but the 75B accept the Kadet Kits now being made, etc. (There is no "A" model CZ...) The "B" designation indicates that the gun is equipped with a Firing Pin Block.