A few comments on the softpedia list...

JackLab is no longer in development.

Musix GNU+Linux is good, but a inclination toward Spanish language instructions can be trying.

Ubuntu Studio is well supported, and contains the latest versions of all the applications. I use it because it is universally compatible with most accessory software.

LMMS is not an O/S, it's a full-feature application that is installed within your Linux O/S.

DeMuDI is no longer in development.

Dyne:bolic has not been updated since late 2007, so it's applications are dated, but it is conveniently upgradeable using it's "Dyne modules". This would be my choice of a lightweight audio O/S.

Presently, 64 Studio is the professional's choice. Very complete, and in constant development by industry experts.

StartCom looks cool - I know nothing about it.

Apodio is now based on Ubuntu, so why not just go with...Ubuntu...?

m-dist is another O/S with older versions of audio applications - I would be concerned about it's compatibility with recent software.

just looking for clues...
Oren.
http://www.masteringmatters.com