I had the same view about ubuntu for a few months... until a couple of
weeks ago! I don't feel they give themselves enough time to test.
Opensuse test their new version for six months - with a new version
release every 8/9 months. BUT they still have problems and their
repositories are nothing like as well defined as ubuntu. As Gobby said
in one email, after trying a few others one comes back to ubuntu.

Each distro has its drawbacks and for me ubuntu's big advantage is the
documentation, this yahhoogroup and ubuntu/kubuntu forums. I was going
to try mepis but there is little documentation and i've decided to
stick to ubuntu LTS versions