Hi Jean,
the equivalent on your 5000 is loading just the sequencer file with 10 songs. These could be multitrack sequences like midi files or songs using the preset styles or custom section. Once the 10 songs are in memory they are quickly selected similar to the g800.
Also there is the midi direct play available which requires no loading time.

Both of these functions are improved on the 6000.

usb is an excellent system, I have camera, mp3 player, card readers, printer, scanner etc. Also a usb 2 hard disk which is the fastest communication possible at this time.