Just throwing my bit in as not everybody knows this.
The Xbox is capable of mounting xiso directly from hard drive using attach.xbe. There isn't any reason to extract/decompress your xiso files simply drop the xiso into the (GAME FOLDER) along with attach.xbe (renamed to default.xbe) and a nice default.png and you're done!
UNLESS, you want to play MGS2 or Jade Empire then you will need to use xiso split beforehand.
Most of the tools I've mentioned are available in rocky5 github.