The Rock and Ice Ultra starts in a short 35 minutes. I spoke to the boys earlier and they sounded excited and ready to finally get going after months of training. Temperatures are in the -20 to -30 C range which is perfect for them. Any warmer and they would have to start taking off the layers they have grown used to training in and any colder frost bite becomes a bigger concern.
Shaun will be running the first leg (~10km) and Trent will take the second leg (~6km) . Shaun will follow with his long leg of about ~24km and Trent will finish it up with with the final 30km. I'm off somewhere in my calculations but its something like that. They are thinking its going to take them somewhere around 8-9 hours...all depends on the conditions and what kind of pace they can maintain.
You can check for live up dates on Sleep Monsters. They already have some pre-race coverage posted from the last few days.