There is no need to even discuss this further even though not one of us has heard every no-name orchestra there is. The personal pronoun 'you' used in the discussion below addresses no one specifically.
Incontrovertibly, the advantages of the VSL are: a) Intonation (try and get that with anybody that you can get your hands on, especially if your work is not just spiccati and brass-drones), b) Metric/Rhythmic accuracy (try and get that with anybody that you can get your hands on, if your work is not just spiccati and brass-drones), c) The quality of the instruments themselves (try and get that with any 4-tier and lower orchestra), d) Musicality in the single pitches that constitute the samples (incomparable except with the best players around), e) Infinite forgiveness for your uninspired composition, unacceptable orchestration, blundering voice-leading, illiterate use of instruments, etc. (try that with almost any orchestra) and -most importantly- e) The unlimited "rehearsal" time (really try and get that with any orchestra - unless your father owns it).
The advantages of real orchestras, any live orchestras are: a) Live instruments, live performance (I don't care how great a programmer you are, I can tell the difference, easily in most cases), b) Humanity in the playing (I have experienced this in even the most amateur ensemble I've worked with. I have cringed at every other aspect, but the human feeling you get with a live ensemble I have rarely heard approximated with samples), c) The unlimited amount of nuance (dynamics, etc.) in the same articulation.
So, if you are recording a work for demo purposes, let alone for a producer, which of the above would you choose, VSL or live orchestra (not the Berlin Phil., the orchestra that you can get your hands on)? If you could ever have only one recorded version of your work your whole life, which of the above would you choose, VSL or live orchestra (not the Berlin Phil., the orchestra that you can get your hands on)?
Having done both, and not having been fortunate enough to be commissioned by the Concertgebouw, or given generous sessions with expensive professional studio orchestras, I take the electronic version of my works as overall closer to my compositional intentions. Be that as it may, I always welcome and am excited (and scared) everytime I get an opportunity to work with a real ensemble; way more thrilling than sitting at home drawing articulation lanes...
And we should not forget that -as with orchestras- the skills of the individual musician/programmer will yield results of very different quality, even when using the same VSL samples!