Such big labs usally have a supply of liquid He anyway - some even have there own recycling system. Still it is expensive to operate. Usually on can refill the cryostat with new Helium. So there is no need to warm up the setup so often. Transfering liquid He from one container to another is not simple, but it works with well insulated tubes.
With liquid He one usually can get very stable temperature and no problem with a power outage. The cryocooler also needs quite some electricity and maybe service every few years. The cooler may also produce extra noise.
An interesting question would be if one could get away with liquid nitrogen and high temperature superconductors.
I think these might be interesting.
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