There are times you need to bring up a domain controller at a remote site. Either to take over the from the current Dc on a temporary or permanent basis.
For a permanent basis, it is best if you can use a physical machines. You can beat the replication traffic jam by backing up the current DC system state and ship the backup. The backup when restored to a simple Windows folder can be used for DCPROMO /ADV. This will pick up the contents of the local file when promoting the local server as a Domain controller. This form part of a baseline for the new DC, so that all the objects do not need to be replicated.
The downside is that you need to secure that CD from being passed around.
Details on using the ADV switch here.