First link is the 1 I have. Although I paid £45 from my local ASDA!!!
Whatever you do, dont be tempted by the cheap ones on ebay. I bought a cheap 32gb on ebay for £10 and it broke into pices inside my RNS510. Had to fish 2 bits of plastic out from the slot with a paper clip!!
Bought the ScanDisk and had no problems with it.