I have been running Bullguard Backup since 2011 for carrying out incremental backups of my systems to a NAS drive. A couple of years ago Bullguard stopped support of the software when they replaced it with a cloud-based something or other which I didn't want to use, so I happily carried on using the old unsupported software until something went wrong last night and I now appear to be locked out of my account with little hope of getting back in (I spent ages on the online help this morning to no avail).
The thing I liked about Bulguard Backup was that it kept the files as is in their directory structure rather than wrapping them into a single compressed prorprietary file which can only be restored via the software. This makes it very easy to restore a single file, either from the latest backup or an earlier incremental version, and for other members of the family to access photos, documents, etc. from the most recent (i.e. nightly) backup on the NAS. My Sonos speakers also access the most recent music backup from the NAS.
I've been looking for something similar (free or not) to replace BullGuard for some time, but nothing seems to work in the same way (I've just run a test with AOMEI Backup).