During winter, my FLI ML8300 hit -48° without trying, using 78% power. It apparently will go to -53°.
I have not used it recently (not for want of wanting to!), but I believe it will also do -30° in summer. Great thing is it get's there fast too!
Best cameras I have EVER used - make SBIG's look like Box Brownie's in comparison
(half joking... I like SBIG, but LOVE FLI)
I run ALL my frames and cal frames at -30° set, as I KNOW the cam will achieve that all year round.