I am seeking technical advice in order to help an existing customer that is looking at replacing their old Tape Library with an immutable Object Storage based repository in the cloud. One of the requirements from the customer side is that the public cloud object storage provider they will be using is Google Cloud storage.
Regarding Immutability, if I remember correctly you will support it as soon as Google Cloud Storage will support object-level lock.
Now regarding the choice between using Direct Copy to object storage or a Scale-Out Backup Repository, although the protected environment is relatively small (currently under 50 workloads), I personally like the possibility of archiving GFS backups to a cheaper archive tier the more they age out, so I would prefer using a Scale-Out Backup Repository over Direct Copy to object storage. In fact, the different storage tiers reminds me of the different sets of tapes that are currently being rotated.
Now the million dollar question

Any information on this matter will be greatly appreciated.
Kind regards,
Massimiliano