Replication is rarely the solution to poor wan links in MOSS - and MOSS deployment support over WAN is not good. Bear in mind that as soon as you replicate content DB's or sites and have them attached to another site collection in a remote farm you have a possible synchronisation issue unless your audience is read only.
A decision to replicate has to be based on planning with a consideration for WAN link data consumption when adding a MOSS farm. What's the impact - you need to know the volume a link has to carry before you deploy a farm, as that should form part of your planning exercise to see if new working practice when using MOSS will swamp your network, and it will if you do not plan it up front. Simple rules like how many read and write operations per day of a typical document size are going to travese our network should be at the front of your mind. Can the doc converter service help me, can I use publishing to offset traffic - what can be anonymous to offset load etc etc.
Also, if you do chose to replicate - how much data needs to go from one site to another or vice versa and before you decide that have you looked at the options like ISA server caching requests etc. and of course the possibility of harnessing WSS instances at remote sites for collaborative working and consolidating search or shared services centrally.
One other thing to consider is to have two farms in this type of low bandwidth scenario and use content publishing to replicate fixed data (like rarely changing HR policy) between sites, but there are many factors to consider (cost and techncial complexity of course can make this prohibitive). If this isn't an option and you must replicate then take a look at DocAve from Avepoint as it can do two way replication with synching.
http://www.avepoint.com/products/sharepoint-administration/sharepoint-replication
I've not tested it (yet) but I hear its a fine fish in a river full of slippery eels!
As usual Joel Olsen has a word to say with respect to replication, more for redundancy than in a low bandwidth sceneario, but also as usual the words do carry a lot of value.
Read more here:
http://blogs.msdn.com/joelo/archive/2007/04/02/replication-and-high-availability.aspx
and here:
http://blogs.msdn.com/joelo/archive/2008/01/17/global-sharepoint-deployment-partner-solutions.aspx