Dan, the main thing you want to calculate with vReplicator is the time it taken to scan the VMDK files for changes. If you estimate based on a scan rate of 1 GB a minute.
If you have quite a large amount of data to replicate it can take a very long time to do the scans. More bandwidth or a small rate of change will not improve the speed of the scan and the load on the COS. The more hosts you have the more you can spread the load.
Often people want to do a replication every 15 minutes but if it takes 20 minutes just to scan a 20G OS disk this is just not going to work.
Have you tried the support forums for Vizioncore?
Considering awarding points if this is of use
Rodos
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