I clean installed RC1 on two 500GB disks 10 days ago, loaded data on and ran backups for 4 machines. This left about 200GB free in the pool. This seemed a little low so I installed another 500GB disk and added it to the pool
After a day of on / off balancing the system disk (C: SYS) is full - Used space : 20GB, Free space : 0 Bytes.
Looking at the drive I have 16GB of log files !
I came across the blog detailing this issue but never expected anything like 16GB's worth of files.
Keep an eye on those log files guys ...