The B models are the firing pin safety models, minor changes from the original.
The D models are decocker models, dropping the hammer safely unlike doing it manually on the rest.
Personally I don’t like the decocker, but that’s from 30 years of 1911 use and I will carry the CZ with the hammer back and the safety on, condition one.
No less a personage than the late Col Jeff Cooper lauded the CZ75 back when it was almost unobtainable, only lamenting the caliber.
You will note that the Bren X pistol that was so favored by Cooper for its short life, was a copy of the CZ only chambered for the 10mm and .45acp.
I keep meaning to pick up a CZ97 in .45acp but never have the cash with me, probably a good thing. There was an experimental model made in 10mm, I await its release. Probably forever, but I’m waiting.