FIREBALL from Escient is effectively a pre-programmed PC. Similar product is available form
Imerge . You should be aware that the claimed 700hrs of music is only possible if you are using 128kbs compression mode, which would be far from audiophile quality.
Check if the unit supports loss-less compression modes and that the album/track info is download-able from the Internet.
Also, ask them explicitly what audio hardware is used as some of this units have been associated with very elementary sound cards. Always opt for the largest hard drive available as those get filled very quickly.
The price of FIREBALL or Imerge Sound Server should be compared to a price of buying a generic PC with (but paying attention as to what components are selected) that would cost you $1,00 to $1,500 max for high-end choice. Good music management software can be found for free or around $100. On top of that you need to and the cost of your time and the learning curve.
At the end, if the time involved is too long or your cost per hour is too high, it may be cheaper to buy a ready made solution.