NetNewsWire is beginning to choke for me because I have a large number of feeds. I was using it today and when I pressed Alt-K to "mark all as read", it beachballed on me and I had to force quit. This has been happening more often recently as I've added more feeds.
Same here, tried both and sticked with Miniflux that seems on the lighter side. I don't really need the web interface or an app, because I channel everything towards a Telegram bot, where I read the feeds: a glance at the title, "Instant View" or long read if needed.
Who old enough to remember when everybody was syndicating all their favorite RSS feeds on their own blogs, and then some joker posted a blog entry to his own RSS feed with a title like "What happens when you put an unbalanced <BLINK> tag into the title?", and the ENTIRE BLOGOSPHERE started blinking?
This is what I use, and I also have Readrops on my phone that syncs back to my FreshRSS instance. Makes it really convenient to have a lightweight reading app where I can submit new feeds to it and have it sync back to the server.