I''m missing familiarity in the bottom panel (even after the mirror shell extension). The thing that made using Mint so comfortable. I never looked at Gnome 3 on Ubuntu, but can say if this is better than that, it still needs a lot of work to make it back to where it needs to be as before.
There are other problems but I guess they are RC related. The lag when opening programs, when trying to view pictures, open VLC, close the Systems Monitor, all annoying. Whenever I wake my laptop out of suspend I have to kill Skype and restart it. Twice when waking up the OS did not recognise mains power and I had to reset my machine.
Dell Inspiron 1520 - T6570 2.1ghz C2D, 4 gigs ram, integrated Intel 965 GPU, Intel replacement wifi card.