Perhaps best feeling plastic cards, IMO, are the Regular formula, "Non- Platinum Acetate" Modiano cards.
A few years back, because of the Popularity & Casino use of Kem ( Cellulose Acetate), all the non-Kem major plastic brands were suddenly tripping over each other to get the word "Acetate" on a line of their own cards, by trying other types of plastic "acetates", some brands I think also just started to put the word acetate somewhere in their fine print just to keep up with others .
There were posts about early Copag, Modiano ect acetate decks being brittle and cracking, and other issues.
Modiano seems to have worked out the kinks in these newer formulas, but it's still mostly a marketing gimmick, they're fine, but I don't feel the acetate versions of these major brands are any better at all over their "regular" plastic decks.