Nas recommendation - reliable ecc nas

[Enquiries]

I'm looking to buy my first NAS and would appreciate your expert advice. My primary goals are:

- Reliable data backup
- Plex media server data source
- Potential Docker and VM hosting
- Strong focus on data protection

I'm planning to start with two 12TB drives and potentially expand later.
I already have an N100 mini PC for Plex transcoding, so I'm mainly seeking a robust storage solution.

Which NAS operating systems is the most reliable ?(Quts hero, TrueNAS, Synology BTRFS).

Could you recommend a turnkey NAS with ECC memory around £1000 (budget includes 2x12TB drive)?

If budget is too small, i would also accept recommendations under £1500.

Thanks in advance for your help!