ALWAYS buy a high speed SD card, and make sure it's SLC not MLC. People who have bought the cheaper MLC cards have reported having problems.paranoic said:
I use 2 ByteStor hi speed 1GB SD cards which I got from Amazon, and 1 A-Data 4GB hi speed SD card which I got on eBay.
With the larger memory cards make sure you don't have more than a total of 512 files plus folders - the RNS-E will only use the first 512 if you have more.
The RNS-E is also more fussy about characters in filenames than Windows (e.g. you can't use the ! character).