First off let me re-enterate, bandwidth to transfer a little.
Bandwidth is like a highway with so many lanes, the megs per second mps is how many lanes you have. For example you can have 5000 cars go through your highway but if you do not have very many lanes they will slow down or even stop.
This is how bandwidth works.
The other factor is how your highway gets you from a to b like cogent takes the scenic route to avoid toll charges, Verio does the same but not as bad. Most pay for close to full access when finding the fastest path.
Even better is a highway that appears out of nowhere that gets you there even faster. This is what a redundant bandwidth connection does. It takes over of the main connection is too slow.
Imagine going to vegas and when the traffic piles up another highway drops from heaven for you to hit cruze speed again on
More info and how to calculate banwidth to transfer:
http://www.dwhswebhosting.com/bandwidth.htm
If your going big on traffic then talk to you host it could save a issue later when your in the middle of your campaign.
Good luck!