In reading the <a href="https://www.vmware.com/support/srm/srm_releasenotes_5_0_0.html">SRM 5 release notes </a>I came across an interesting and unexpected limitation that may reduce the viability of VMware Replication for some customers:

<strong>Large Disks Perform Full Sync Unnecessarily</strong>

When disks larger than 256GB are protected using vSphere Replication (VR), any operation that causes an internal restart of the virtual disk device causes the disk to complete a full sync. Internal restarts occur any time:
<ul>
<ul>
	<li>A virtual machine is restarted</li>
	<li>A virtual machine is vMotioned</li>
	<li>A virtual machine is reconfigured</li>
	<li>A snapshot is taken of a virtual machine</li>
	<li>Replication is paused and resumed</li>
</ul>
</ul>
The full sync is initiated by ESX, and any resolution to this issue would involve an update to ESX. These syncs involve additional I/O to both the protected and recovery site disks, which often takes longer than the Recovery Point Objective (RPO), resulting in a missed RPO target. To avoid this issue, use smaller disks.