We did chicks between Hamilton, Ontario and Pocatello ,Id. In a DC3, heavy crewed, O2 equipped for the MEA's over the Rockies, and an extra Janitrol heater in the back to keep our charges toasty,and warm, it went off without a hitch, I will never forget that sunrise over the Front Range at the MEA about 2000 agl over the peaks, we had drift down alternates in every valley, we were way above our single engine ceiling in case we had to cage one. Not really a horror story it went really well.