I've owned both, and recently switched to Synology. QNAP's software is functional, but it has become increasingly user hostile as they try to address security gap. Increasingly intrusive notifications and nagging for updates. Anti-malware (that ties into the intrusive notifications) is not a bad addition, but has been shoehorned in.
I also value ease-of-use and management for a home office, so I'd generally recommend Synology for home office. Performance, especially on 1Gbps networks is going to be comparable, and they both support docker containers for things that aren't pre-packaged. I've been able to hook both up to B2 for off-site backups and they run without me even thinking about it. It really boils down to Synology's software has more polish and is more Apple-like to QNAP's Windows/Linux-like approach to the OS.
I don't use this functionality, so I can't say how it works, unfortunately.
EDIT: I will say one thing that I like about Synology on DSM 7 vs QNAP is permissions management. QNAP's permissions are a bit of a black box and I've run into issues with packages/containers creating files that cannot be deleted by an admin user over SMB who has full access to the share. Whoops. Meanwhile, DSM 7 seems to create dedicated accounts (and shares) for packages, which took me a bit to wrap my head around. That said, once I did, it made a lot of sense from a security perspective.
