I think you're referring to the actual trigger shape/profile - the "older" CZ85 trigger is different that the newer one, which is also installed on "newer" SP-01 Shadows. I'm not sure if I've handled the "newer" version, but I did swap out the trigger in my Shadow (which was the old style Shadow trigger) for the "older" CZ85 one - it has a longer radius, and doesn't have the pointy/sharp feeling edge at the end that the original Shawdow trigger had.
It's simply personal preference; if the trigger you have isn't uncomfortable for you, installing the old style CZ85 trigger may result in a "meh".