I would say it would be much easier to load via software when possible.
I have loaded both DM TRS systems, the tower and ground frequencies, Thunderbird frequencies, ACC generic use frequencies (which cover all of the aircraft at the show), Civil Air Patrol, Independant Squad Radio frequencies, and the discovered frequencies, i.e. the Air Boss. There will also be "discrete" frequencies in use for air-to-air chatter amongst formation flying.
I will try to update while at the show, assuming my cell phone cooperates