- dual micro-SD card slots for up to 512GB of storage
- high-quality DAC
- support for all the formats I use
- good battery life
- frequent firmware updates
Unfortunately, the device I got has to go back. It's probably defective, but it also has significant UI problems (even in firmware version 2.6). Here's a summary.
- turning the device on almost never works. I always have to reset it (hold the power button down for 15+ seconds) and then try to turn it on (hold power button down for 2 seconds). Most of the time, that doesn't work and I have to do the whole operation again. Occasionally several times. This means it takes 1-2 minutes just to get the device ready to use. iPod = instant, and it always works.
- the hardware buttons do not work when the display goes to sleep. To turn the volume up or down, pause, play or skip, you have to click the power button, then the hardware button you want.
- Sure, you could set the display never to go to sleep, but you lose the battery-saving benefits. And the default behavior is for the display to go to sleep, which means the out-of-the-box configuration doesn't work the way you'd expect, and requires two clicks to perform any function.
- the two points above often combine for maximum annoyance. When the display goes to sleep (or the device enters some kind of low-power mode that lets the music play), and the power button doesn't work, which means you can't pause / unpause / skip / adjust the volume. The only option is to reset the device (hold power button down for 15+ seconds), start it up, try again if it didn't work, and make your change.
- Except when the device comes back from a reset, it doesn't remember what track was playing, so you have to browse your library all over again, find whatever you were playing, and play it again.
- browsing the SD card or the library is impossibly slow.
- The jog wheel scrolls through the library at the same speed, no matter how quickly you're jogging. On the iPod, after a certain speed, the scrolling speeds up and skips whole letters in the alphabet all at once. On the Fiio X5, if you have 500 artists and want to listen to Zimmer's Hole or Zoe Keating, you'd better have a sandwich at hand, because it's going to take a while.
- When you're tired of Zimmer's Hole and want to switch to Frank Zappa, each step (tracks -> album -> artist (Zimmer's Hole) -> scroll -> artist (FZ) -> album -> tracks) takes 2-5 seconds. So switching to an album by a different artist can take up to a minute.
- Because the device needs to be reset constantly, loading up two different albums is a multi-minute ordeal that simply doesn't happen on the iPod or any smart phone.
It's a shame, because the audio quality is truly fantastic. But the device itself is unusable.