Mine came from Turner's - even cleaner than yours, matching parts, very accurate.
I added the slide catch for convenience, and a Harrington firing pin for a better trigger pull (yes, the decocker issue - the decocker was broken when I bought it, anyway). I'm very happy with accuracy and the cartridge.
I'm contemplating adding the modern mag release per the plans on the CZ users' website, but it needs more time than I usually can spend on a project. If you practice enough, the heel release becomes quicker to use than it is at first, but still . . . anyway, it's my CZ and I like it.
BTW, if you want a good modern kydex holster and mag carriers for the CZ52, Spetzgear (http://www.spetzgear.com/
) made a set for me. I recommend Walter's work most highly.