Hi Dave,
First congratulations with the live performance. That being said, I mostly agree with everything said here so far. Paul stated the sloppiness of the live version, Anand calls it human...
The interpretation is definitely different but they both have some interesting points of view. The thing that strikes me most is the recording area. The VSL-version has a clear open acoustic, whereas the live version is rather dark, with a very short reverb tail (recorded in a rather small room or without distant microphones?) That makes the overall sound a bit dull, because it isn't supported by the natural hall effect.
The piece is a high quality composition with so many playing techniques organically inserted in the thrilling musical story. Hence it is obvious that musicians will likely build an own vision on the performance. As a composer you had your view conceived by the natural flow of composing with ideas and structures, techniques and expression. This experiment might show clearly that these processes aren't the same for all participants in the final creation.
If I had to choose (as to 'quality'), I'd have a slight inclination to prefer the live version, despite the so called imperfectness. Not that I don't like your virtual version, quit at the contrary. It is absolutely the winner as to correctness, sound, ensemble balance and skillful handling of the samples and articulations, but I miss the human feel a bit. Probably becuase I was working for many years with my own chamber orchestra and because I was so used to discuss the interpretation with my musicians. In most cases the final version was a sort of mutual agreement between me and the players. They had their vision, I had mine and we managed somehow the find that delicate balance. That is an interesting point of vue for this experiment as well. Have you confronted (after the recording) the musicians with your version?
Thanks for posting this interesting topic and for the beautiful music,
Jos