Exchange servers and branch offices

Wondering what the recommendations are for exchange 2007 in terms of setting
up an e-mail infrastructure.  Main office bridgehead,
Should remote offices (there???re a total or 5 locations, 140/180/90/50/with
main office with over  500 users) have their own Exchange server? This is the
way I???ve set things up with an Exchange 2003 environment.
Users are not limited to the 200 meg individual mailbox size, many mailboxes
will exceed 1 gig.
Concerned about the ost/syncing across a dual T1, need the highest
performance most reliable solution.
Mike

it is a tricky one with Exchange 2007 because you would waste a lot

it is a tricky one with Exchange 2007 because you would  waste a lot of
hardware for a dedicated Exchange server.
If you have a few applications out there you may well look at Hyper-V
and having one physical with a local DC, Exchange, SQL, etc. etc.
server guests.
You're either going to spend money on the WAN or you are going to spend
it on servers and software. You have to make your own judgement on
which is the right route.
I would see about the WAN first and then deploy an Exchange server
only if it proved essential.

Thanks for the reply Mark,If money was less important than getting as close to

Thanks for the reply Mark,

If money was less important than getting as close to 100% in terms of the
most reliable e-mail system company wide, would you place an Exchange server
in locations where employees exceed say 25 users? maybe 50.

Today many professionals expect e-mail communications never to fail, always
up and available 100% of the time, having access to past e-mails, calendar
items etc. at anytime is critical. Users think their Inbox should be able to
grow to an infinite # without any consequences.

Off the top what concerns me is the OST stuff syncing over the WAN when a
users Inbox is 4 gig, the performance hit maybe unacceptable for most.
Thinking there is other issues well.

I would start looking into implementing Exchange 2010, if the bandwidth

I would start looking into implementing Exchange 2010, if the bandwidth is
concern you may want to keep Exchange server in each location, the I/O and
redundancy are no longer  the issue  in general with Exchange 2010, much
faster and lighter application and you can provide better mailbox experience
to your users.

To be honest 200 Meg is way to small for a mailbox if you consider e-mails
today with more towards into multi media and other attachments. Anyways as I
said,  looking into investing Exchange 2010 is much better take in my eyes
for many reasons.

best
ocd