If you're getting Copags and you are worried about slickness, pick up the Signature style Copag's (see below).
http://www.chessset.com/copagsignature.html
These are NOT slippery, and actually have a grippy texture that other Copag styles AND Kem's just do not have. If you buy them and disagree with my "feel" assesment, I'll buy them off of you as you can never have too many (I have 2 set ups (4 decks) now with 1 still sealed). They only come in Bridge width and super index, but I have not found ANY plastic card (Kem's, other Copag's or Dal Negro Grand Slam's) with this feel in bridge width. It would be great if Pokerchipsreview would do a write on this particular card as it would be great to have it documented that all Copag's are not created equal. And I do agree that the other Copag's that I have experience with (1546s and Masters) are somewhat slippery.
Now if you're a poker width man, I say go with Dal Negro Freedom's hands down. They have a lot of the stiffness and feel of a paper card but they're plastic. These cards are great. They're not as flexible as Copag's and Kem's (or even the Dal Negro bridge size card called Grand Slam's) but they can still take a bend like a plastic card should and even the veteran poker players (who are anti plastic) like them.