The great thing about MEPIS is that it is based on Debian. I believe that
it is KDE based, too. Which is doubly good, IMO. I also like Warren
Woodford and the community. It is a small distribution, but since it is
Debian based it can act like a bigger one, having big repositories and a
larger community that is closely linked. The problem is that Kubuntu is
bigger in all respects and everything is up to date. If you do not need the
biggest and can settle for big and if you do not need the most
recent versions then MEPIS could be just the thing. For someone like me
aptosid is better because it has Debian ustable as its basis, just like
Ubuntu. I am also not partial to rolling releases but that is just me. I
like looking forward to the next big thing.

MEPIS is definitely worth a try for anyone disaffected with Ubuntu. Kubuntu
on the other hand is not linked with Canonical any more and the only reason
to switch from it is if it is not working for you, IMO.