I'm running MSR / OpenLUUP on an old Intel NUC with Debian Buster. The HA is now on a Raspberry Pi 3+ because it was simpler than wiring up a 4. All my my Pis are powered by POE splitters, which is nice 🙂
Totally get the concern about the SD cards, but in honesty I have about 6 Pis running Volumio, Kodi and Minidnla and so far touch wood no issues to report. All on SD....
Performance of HA is not a concern so far. I have a NAS (1) that will store my backups nicely.
C
(1)Bloody thing has died tonight. I'm shopping ATM!