NAS question - Use the NAS to just to host media, or also to run Plex server too?

So I’m looking to invest in a good NAS. Currenty I have a really simple slow (XTreamer) NAS which I just host my media on. Plex server is then running on a Dell I5 Optiplex 3010 PC (my server). This works fine if a little slow ff and rwd’ing videos.

So I want to replace that old NAS with a better one, at least making use of the gigabit lan I have (the old one isn’t gigabit). But the first question would be, would it make sense to get a NAS capable of running Plex server, or instead keep that on that PC?

Generally I watch everything as native via Plex on my Amazon Fire TV box, but a couple of other TVs around the house on homeplugs require me to watch video at 720p (instead of say the original 1080p 10gb MKV file)!

From what I understand, to get a NAS that can also transcode for Plex well, is difficult, so would that mean it would make sense for me to keep with my current approach with the PC hosting/running Plex?

And if so, I assume then with a good NAS running over gigabit, that would then boost Plex’s performance, especially with ff and rwd (which at the moment is quite clunky at times).

For over 2K you can get an I7 Qnap that will do most everything .
But the 500-1000$ price point you will have issues streaming your 10GB MKV media.

What I suggest is buy the most expensive 4bay Intel based NAS you can afford.

If/when you find that does not have enough grunt to do your streaming , keep it as storage and buy a Shield or hi end NUC to use as the server!!