I've just checked amazon again for the 8gb sansa clip. the original price on one was £119, now £40. I cannot understand why, unless it's an old model(?). I'm assuming this would be the better one to buy over the one that was £50, now £49....??? any feedback would be appreciated

Hello. I've finally decided that I'm going to buy the Sansa Clip portable player. Checking amazon.co.uk there seem to be 2 kinds, the SDMX18R - 004GB - E57 SDMX18R - 008GK -E57 wondering are these the same? also, I'm guessing I should definitely choose 8gb over 4gb, right? (btw...