I ran Ubuntu Touch a few years ago, when Canonical supported it, and eventually gave up because I didn't think it was polished enough.
I came back to Ubuntu Touch a month or two ago out of frustration with Android, and it is much less buggy than it used to be, I'm very pleased with it.
My only issue is that the best phone (AFAIK) to run it on is a OnePlus One, which is quite old and slow compared to more modern phones.
But it's such a breath of fresh air to be using a mobile OS that isn't nagging you to sign in to Google, sign up for a Samsung account, install the latest OneDrive app, accept location sharing, agree to the terms and conditions, etc. And it's all open source and hackable, the Terminal app is a first-class citizen. It's great.