Get the new items the Xunsound XS01 and F Audio S1! Here together with Ruizu A50, front and back

Here with same carrying case, provided with both XS01and S1. Buttons and display looks same. S1 is screwless, with acrylic finish on front and back very well made. Edges not rounded but not too sharp. XS01 has rounded edges in height, but on top and bottom edges are rough and quite sharp, where the removable panels are. So I want to look inside XS01...

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Opamps are Opa627ap, and notice the embossed writing under the play/pause button, says PALY/pause haha.
First observations... both no have gapless playback, S1 have Bluetooth, equalizer (so so quality, and anyway I never use EQ) and an "in" jack that I don't know for what, and resume play working well.
XS01 is more audiophile, no BT and no EQ, two out jacks, a PO out very powerful and a LO out made for sensitive, low impedance phones, actually too weak for my Ultimate Ears ue900s, so I go with PO (that I can't use at max volume, too high!)
The UI is simple on both, S1 is little more complicated due to the lack of power on-off menu and back buttons, the central button works as power on-off by long press, play-pause by click and menu access by short press (around half second) while the left button works as Back (the right button is delete song when in the track list)
A drawback in XS01 is rew-ff, it depends on track lenght... the longer is the now playing track the faster is rew-ff speed! In case of long tracks, 30-60 or more minutes, rew-ff may skip several minutes every second making it uncontrollable, and elapsed time indicator become wrong... Another downside of XS01is resume play not supported... is selectable in menu on or off, but if is set off when turn on the player restarts from the first track in the folder ; if set on restarts from begin of track that was listening to, not from the point where the track was interrupted. Hope a firmware update...
Display clear with white writing, not blue as it may appear on pictures.
Very first impression on SQ... S1 is very good, XS01 is great, that makes forgive the downsides!