I am thinking about using an RPi 4 (4 or 8 GB RAM) with one or two HDDs in a RAID enclosure (connected via USB) as a NAS using OpenMediaVault.
It would be primarily used for storing and sharing my music (mostly FLACs, about 1TB, growing steadily), some films, and as a backup for important data (backup does not need to be automated, I am fine with doing that manually).
I'd access the music with foobar2000 from either a laptop or a desktop, and I don't want to experience significantly longer load times compared to having it stored on a local HDD (current solution).

My question is: Would a cheap NAS like the Synology DS220 be a better solution in terms of performance? Does less RAM on the DS220 (2 vs 4/8 GB) impact the loading times of large folders = albums/discographies?
I like the RPi for the easy upgradability in the future (using upcoming RPis or bigger RAID enclosures) and the better price.
What do you guys think and recommend?
What is the best solution for my insufficient local drives?
Are there obvious bottlenecks?
What drives would you recommend? WD Red? Seagate Ironwolf? Toshiba NAS Drives?

I hope this is the correct subreddit, sorry if not. Thanks in advance for any help!