Hi tom,
yes i know that ubuntu is based on debian.
In the past i made the experience that ubuntu (lts) is much stable than debian.
We are running multiple gitlab-runner under debian stretch, they had many kernel panics but not under ubuntu 16.04 (lts).
I am not an ubuntu fan boy but these are our experiences.
Since systemd a lot of our server had problems during booting under debian but not under ubuntu 16.04 .
I know these are subjective experiences but it looks to me that ubuntu is making a greater effort to find solutions for current problems.
Best regards
Masi