A review of MIDI SONG and Registrations

[sugarplumsss]

If I had more solo gigs, I would be further along on this journey of playing along with MIDI songs.
As it is now, I have two somewhat chaotic methods of choosing MIDI Songs
1 Save a MIDI within a Registration
2 just cherry pick directly from Song mode, by passing Registrations

Some observances about on the fly Song mode edits during a gig. If Song is on the USB it is 10 seconds ( almost an eternity ) before t4 clears out of Mix mode and back to main screen

I am wondering if HD is a better place for 120 MIDI and registrations
I get a bit confused about where to save sometimes ... USB or HD?
I had a new HD put in..
I am worried ( lack of knowledge ) about filling HD to capacity.

Save MIDI songs as Registration still a better idea?
I am, sorry my questions reflect my vagueness on these issues .
Any thoughts will help.
Thank you

[Hammond Yamaha]

Save your midi song as part of a registration because in the reg, you can have your keyboard settings ready to go and no key punching.