My comment above is now obsolete, it is just that you have to tell ubiquity that you are using dmraid (there will be a UI for this later) by running these commands beforehand:
sudo mkdir /var/lib/disk-detect
sudo touch /var/lib/disk-detect/activate_dmraid
Then ubiquity will only show the raids, and no raw devices. Nice!
My comment above is now obsolete, it is just that you have to tell ubiquity that you are using dmraid (there will be a UI for this later) by running these commands beforehand: disk-detect disk-detect/ activate_ dmraid
sudo mkdir /var/lib/
sudo touch /var/lib/
Then ubiquity will only show the raids, and no raw devices. Nice!