depends on what the moves are.
if they're of shuffling, dealing, etc you may want to bring someone in that's had a lot of experience doing those things. card moves can sound dramatically different in the hands of a pro vs in the hands of an amateur.
Business Cards? Post-It Notes? Credit/plastic cards? These are just some ideas, but it also depends upon the action required. Break away from the literal sound playing cards make and think of textures and frequency variances. All the above props offer different tonality, brittleness, frequency characteristics. It's the juxtaposing of various carefully-...
As @NoiseJockey said - difference is in speed.
Take a look at sources. CF card use parallel bus (PATA) similar to old HDDs. But it is not true that they are faster for more pins.
Modern trends are to use less cables (eSATA, Thunderbolt, Ethernet) for flexibility and magnetic and electric shielding.
Based on provided source SD cards are used primarily in ...
I don't know what it is you don't like with what you got, but don't forget all decks sound and act differently, and that different microphone-techniques gives different results! Myself I found a good sound in especially two decks, one Star Wars and one Pondus (a Norwegian comicbook character), recorded with a special tilt on the mic.
One of the truism's of Foley seems to be that things of the right size and shape seldom sound like the right size and shape!
As Stavrossound said, try different sizes and thicknesses of paper and cards to get the right tonality for the scene. In addition to his suggestions, I'd also suggest index cards, or even try old floppy disks if you can find them (I ...