NAS-QNAP or Synology for PLEX?

I’m getting ready to move over to a NAS to install PLEX media server for more storage and remote capability. I have a very large collection of Movies, TV Shows and Music and would like to go 4-bay instead of 2. Don’t want to have to worry about upgrading a NAS.

Anyone out there that has experience with either QNAP or Synology and which would you recommend and why? Best software-easy setup etc.

I’m leaning between the Synology DS-920+ and QNAP DS453D. Ideas and/or advice?