Go with the M3 Simply or R4DS There is absolutely no difference between the two except the sticker on the front both are the same price, have the same menu and do the same things don't let anyone tell you otherwise just pick one out of a hat They use micro-sd cards for storage and are the best in terms of performance - price ratio after that i'd go for the M3 Real cos its the same but supports Micro SDHC or if you want a NAND flash one go for the G6 Real which has 2GB Space and is a reasonable price unlike the DS-X whch is the same and has buggy firmware Hope that helps...