I did an A/B of the free soprano choir against the retail soprano choir today (I bought the Vienna Choir last month), and from what I can tell, they are two completely separate samples/sessions.
In fact, the original downloadable soprano choir is FAR superior to the Vienna Choir, IMO. When I bought the Vienna Choir, I was hoping that the rest of the sections (alto, tenor, bass) were going to be as good as the download version. Alas, I was not too happy with the production values in the retail version.
Specifically: the download version has much more "gliss" between the notes than the retail version. Unless I'm missing something, the retail version just doesn't sound as authentic as the download version. (The retail perf-legatos and perf-legato glisses don't even come close to the perf-legatos of the download.)