[rkaplan]

This is the correct answer. A key reason Rebco is so much better than older alternatives is that it can be cooled to superconductivity using only liquid nitrogen (77K), as opposed to liquid helium, which is much harder to work with.

[foobarian]

Nit: ultimately the new magnets need to be stronger for the same volume no matter how easy the cooling is to work with. That part is just a nice bonus.