Half my team switched to JJ this year, and I do find stacking PRs to be much more pleasant now. We had previously tried out Graphite but it didn't really stick.
I wrote up a little way to use JJ's revsets to make it easy to push an entire stack of branches in one command:
https://crabmusket.net/2025/jj-bough-a-useful-alias-for-stac...