Do many people have problems with freezing? I'm using a v5 board, and I know it had some updates over the past versions... did the freezing problems get fixed?
I think it is more a problem with the overall temp. RJ, designs his stuff to go like -40 degrees or some ludicrously cold amount that no one hope to get to or let alone go outside during =). But on a side note, not me as I live on the other side of the temperature scale in Phoenix, I still think some people like to keep their electronics warm.
My outlook is try it out and if you dont see any issues then either leave them on or power them up like 5 minutes prior to the show. Not sure where you are at in the world, but I again think it falls on personal preference.
Mine worked great left on, so most likely I will do the same for the Christmas season along with the two LE 5's i'll add in the mix.
Also for me I prefer to have them fired up so I can just take my laptop outside and do some testing /modifing of a sequence while sitting in front of the house at anytime and not have to chase down timers or climb back up on the roof.
-JS