Hello. I recently bought on eBay the Nike/Rio PSA[Play 120 mp3/wma player. It has 64mb onboard and a card slot for upgrading to more memory. Rio's documentation say it takes Multimedia Card flash memory, but I wonder if it can also take Secure Digital flash cards. I searched on Pricewatch for each one of those types and in the descriptions they always say that each one can fit into the other's slot. So if they always fit in the slot, do you think the player could just use an SD card, rather than MMC? Where I shop MMC is hard to find, so it would be cool if I could buy and use some SD cards. Are the cards simply interchangeable?? Thanks for your help! God bless...

You can use whichever card you want. The only difference between the two is: SD has a write protect switch and it’s more durable. MMC is much faster, has no write protect switch and is slightly less durable.