Well, I didn't freeze. I'd say with a couple minor changes this setup would be good for the lower 30's. If I had some fleece or something similar on and would have had the UQ rigged up right I would have been great. I think it was right about freezing since there was a dusting of snow when I got up.
I ended up switching to my sleep system after waking up cool after 3 hours. Found out how much difference having the bivy on makes. My feet caught a little of the wind and were pretty cool in the morning.
The insul-bright is great stuff that you don't have to worry about compressing. Could feel where the piece by my feet ended.