I flashed to OxygenOS, and I can definitely say it is an exceptionally stable ROM. There are a handful of issues that I've experienced, but for the most part, I only have 2-3 bugs. I've seen a list that other users are experiencing, but I've never had those.
It is fast, fluid, and definitely worth a try...... if you're looking for that stock Android feel. Coming from mostly Nexus devices, it ruins it for me when a company changes out so many features I like that Google created. I'm glad to be on essentially stock Android with only a handful of extensions and not huge modifications. I can't wait to see what they introduce in the next update.