I built my own unraid server about 7 years ago - I just switched to Synology last week.
I do not want to turn your thread into a Unraid vs. Synology so I will stick to my personal experience which is simple - Unraid can do a lot of cool things if you have the time and patience. If you want something that is easier to figure out, but costs a little more than Synology is the way to go IMO
I had my Synology up and running in 1 hour, it took me a few days to figure out my Unraid. I wanted to get my Unraid to work with UpNp, to do that I had to add files to the boot drive and, in reading folks experience getting UpNp to work with Unraid some lost data because they didn't do it right; on Synology I clicked a button to get UpNp.
Good luck on your choice; there are a lot of different opinions and if there was one right answer everyone would be using it so have fun along the way
My setup - Dune Player / Oppo 95 / Unraid server / Synology 1812+ / Samsung UN75F8000AFXZA