Classic Gnome 2 UI Preffered.
If you think about it, Canonical has been trying to APE apple's OSX UI, adding some variations.
You will find over 9000 similarities between Unity and OSX UI.
This kind of F*^%'s up any chance of a PURELY UNIQUE LOOK AND FEEL for Ubuntu Linux.

Other linux distros were bright to chose gnome 3 shell, a trully unique linux UI experience like no other

The only advantage i see for Unity vs Gnome-Shell is that Unity still supports compiz fusion.

However none of the above next generation Gnome UIs is as mature as the classic Gnome 2 UI (convinience)