Yes, don't do it
Even if i did something weird yesterday
before i installed a fresh RC2
I changed the repositories in Daryna to the repos taken from RC2 and after i did an aptitude update && aptitude safe-upgrade
After 200 MBs of updates, mintUpdate found new updates ... around 250 (or even more, i didn't counted) so, i had a new system.
A new working system
... quite impressive ... (my last attempt to do this with Daryna after Ubuntu 8.10 was out failed miserably
After, i reinstalled a clean RC2 because what i did before was just a test to see what i get from Daryna with Elysa repos
Now i'm waiting for RC3 because looks like i have to wait for a while for the final Elyssa and counting the bugs solved from RC1 to RC2,
gives me the impression that RC3 will be very close to a stable Elyssa.