FW - slicing images and flash

Okay here is my process:

I am taking an image and slicing it up in Fireworks, then putting it back together in flash by loading each slice into a movie clip and then assembling the movie clips (using createEmptyMC to load each slice into by the way).

Here is my question:

Which is more processor intensive for flash - 1) cutting up an image into maybe 12 pieces that are say, 300 KB a piece or 2) cutting up the image into like 72 pieces that are only 45 KB a piece. Or is it the same?

Thanks for any advice.