Stevenmlittle

Hello, I plan on moving over to unraid but have a few questions regarding some features. Firstly what level of licence do I need to enable the use of a cache drive, assuming I do not exceed the 6 drive maximum of the basic licence. To be more clear would the basic licence have the ability to have a cache drive if not what level is needed? Secondly due to the volume of data I have on my existing NAS, I was planning on putting enough drives in my unraid to store the data. Once the data is transferred I was planning to slowly replace the temporary drives with the ones in my existing NAS, once they are replaced I would add any extra disks. Please note that the machine the old NAS is running on will be retired once the data is moved. Would this be possible, any recommendations on doing this differently? Lastly lets say I have an array of 6 2TB drives how would I got about replacing all six of those drives with 4TB drives. Also are there any limits related to VMs and iSCSI shares? Thanks for your time.