As I understand it, for MRI (and other devices which need high fields, such as magnetic confinement fusion), the biggest limiting factor is not cooling, which i

As I understand it, for MRI (and other devices which need high fields, such as magnetic confinement fusion), the biggest limiting factor is not cooling, which is not terribly expensive relative to the cost of all the other equipment (liquid nitrogen is actually cheaper than milk), but the so called critical magnetic field strength, at which the material no longer can maintain its superconductivity. There's been similar progress along these lines as well, but it is not as glamorous -- as the critical field increases, so too may your magnetic fields. By contrast, room temperature superconductors, if they're cheap enough, are way better than even slightly lower Tc superconductors, because they can be used in situations where cooling would induce a prohibitive efficiency loss and expense. Hence the glamor. :-) It could revolutionize instrumentation, power transmission, generator, transformers, power quality, signal transmission, on and on and on... :-)