I have a client that desires a new application for use at several stores in
different cities. He wants "real time" access to all store data and the
ability to continue to run locally even if the internet connection goes
down.

It occurs to me that a local MySQL instance should definitely be
in each store to continue work if the net is down for any reason. But, what
is the best way to synchronize/share data among all of the stores?

From what I have read on the MySQL site, you need MySQL Cluster to do
synchronous replication, but it won't work over a network connection less
than 100 mb.

Is there any hope of synchronous replication using the free version of
MySQL. And, just how stable if the free edition (with it's bleeding-edge
code and such)?

Any that you give will be greatly appreciated.

Thanks!