I used Lit components in a large FE project, enjoyed doing so and am happy with my choice. I don't use the shadow DOM at all.

The project is Converse.js, an XMPP chat client. It's an old project that was originally created back in 2013 with Backbone.js.

I first replaced all templates with `lit-html` when I first heard about that, and then when lit-element (and now "lit") came out, I started rewriting the project to use that.

This app has since been integrated into many different websites that rely on other frameworks like React and the fact that Converse.js is a web component (<converse-root />) makes this easier.

If you're interested, here's the Github repo: https://github.com/conversejs/converse.js And you can demo it here: https://chat.conversejs.org/

You'll need an XMPP account (see https://providers.xmpp.net/ for possible providers).