I very much doubt it would take you 30hrs plus - I recently did a test with 950K and it took around 11 or 12 hours. An overnight transfer would be fine, and that was with an active server including the forum being online. (I used a copy database.)
I can understand where some of your questions has come from. I have been running threads for over 5 years, previous to that I was running ubb (which then became ubb classic).
If it is still required I will do a full answer later today
