Depending on the price I would like to use to replace my Synology, I will strip os and run standard Debian.
Sadly is very hard to repurpose an Synology.
QNAP x86, standard uefi! Can run anything. Been running mine with Proxmox, ZFS, Runtipi and others. Easy GUI setup for everything, Runtipi is just clicking add for various things.
Wait which model line? I never knew one could run their own OS on QNAP
Basically, all of those https://www.qnap.com/en/how-to/faq/article/nas-recovery-guide-for-x86-based-nas There are some older models that can only boot from the DOM, however most newer ones (especially the AMD Ryzen ones, which i personally would highly recommend) have no issue. The early TS-X77 models do not boot from NVME, but that can be overcome with some creativity :)
Hmm, how do I know which models can only boot from the DOM? AFAIK Terramaster NASes don’t have such restrictions.
Consider TrueNAS Scale with mirrored drive pairs DIY.