Sorry to wake this thread up.

But In line of this topic I have a few specific questions.

First a backgrounder:
We have one central BES (single BB Domain)
We have one central SQL DB on or BES (same server)
We have one BES service account
We have more than 40+ Exchange servers scattered worldwide.
latency ranges from BES to the Exchange servers ranges from 10ms (same site) to 1000ms (yes one thousand )

What I would like to know is that, what are the best scenarios for our case?

Would it be helpful if we have several service account hosted in each of the 40+ exchange servers?

Or would it be feasible to install one BES per site (locale)?