To your questions:   1) It's suggested to wait for more reviews to come out and refer to other user's' opinions. 2) The M3 does not support gapless playback 3) We have not evaluated it yet, but we will try our best.

  You can do it with the theme DIY tool for X players. Firstly use the DIY tool to unpack the firmware file, then locate the \str\english\eq.ini and open it with notepad. After that rename the eq style as you like and click Save to save the file, then finally repack the firmware with the DIY...

  It's suggested to firstly set the USB mode to DAC, then connect the X3 to the computer, after that double click to run the setup.exe. If the driver is not successfully installed by appears in the program list, you should have it uninstalled before installing again.