I am curious about the OS and where the library is stored. Is it stored in the internal memory of the X3 or X5? If there were a significant time delay, it would be cool if there were an option to generate and store the library on the SC card itself, such that the DAP does not need to generate one upon insertion. The DAP could run a quick check, and if the library isn't the newest file on the card, it would wipe it out and generate a new one. Also - I assume that all file management on the computer end is just drag and drop file management, correct? It would also be cool to have a simple app for the computer on the user end that: 1) formats cards as needed, 2) supports the drag and drop, 3) generates a library file for that card, and 4) shows the directory structure of that library file. Obviously, I don't know anything about the product, so these ideas might not be relevant.
Very nice ideas you have there mate!
I hope FiiO considers this. Especially the no. 3 he mentioned, whether it's a software or just a library file generator program. At least the effort spent on generating a library file is done seemlessly on a PC, instead on the device itself. This is very useful if you have very large number of music you plan on putting in the X5. Having the ability to create a library file from the device is undoubtedly a must but I think having an option to create it somewhere else should be possible too. :) Maybe sometime I or someone can make such generator for FiiO :). I really think this is helpful.