I'm sure that's desired. But staying inside a range is always difficult, and cryogenic temperatures probably make it harder, both for valve materials and things

I'm sure that's desired. But staying inside a range is always difficult, and cryogenic temperatures probably make it harder, both for valve materials and things like water in air freezing on the valve or ice clogging vents. I'm told liquid hydrogen actually is somewhat compressible, and metals change properties when cold, so room temp and pressure physical intuition may mislead.