what would be your criteria for loading music to the empeg, as evidently having more than one version of a determined concert would prove a waste of space

I would either (a) upgrade the hard disk to fit all tunes, or (b) put the one YOU like the best on the player. It's your music, do what makes YOU happy.

The whole "technical quality versus performance/energy/fun" thing is something all musicians struggle with. The dream of any musician is to capture both at the same time. I can name many examples, though, where the more energetic performance wins out over the technically-better version. This seems to be the norm.

One good example is Andy Summer's guitar solo on the Police song "Driven To Tears". He specifically said in an interview that they did a lot of more technically precise takes, but in the end, the wild, sloppy, out-of-tune, dissonant solo won out because its energy was so tangible.

Even in filmmaking, George Lucas is a big one for energy-over-technical-precision. For instance, there is an infamous moment at the end of Star Wars, as everyone is celebrating in the hangar after destroying the Death Star, and Leia calls out "LUKE!", and he responds with "CARRIE!" quite clearly. It was left in the final edit anyway, because the performers had the best energy in that take.