Well, both players were quite stable up until last week. Â Then something happened with newer builds and the LCD backlight for the X series. Â I'm not 100% sure, but I believe this is fixed now. Â
I think the differences between the two are cosmetic. Â The X of course has the bigger screen and is slightly smaller in size and weight. Â The F series has the button LEDs on the side. Â The X series is very elusive, so good luck trying to get your hands on one, especially the X60. Â (That is unless you live in Aus or Japan

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