I use a Drobo unit that has this thin provisioning feature that allows for the storage volume to grow as you add newer hard drives to it. Basically the OS sees a 16TB volume, but in fact you only have a few tbs (I currently have 2 tb available). As you add new hard drives, or replace old ones, the volume available grows. My question is.. would think work with apple's new filevault 2 external drive encryption feature? My guess is that it won't since FV2 apparently handles drive's partitions differently. Any input would be much appreciated! thanks!