They were overpriced, hard to repair, and the university lab would lose one every few weeks. The consumer grade internal ribbon interconnect harness would usually tear eventually.

Those 3kW to 5kW brush-less servos in the biped dance video are often only 12:1 planetary reduction, and are almost certainly backdrivable. As long as the platform has a safe-fall canned pose, than damage should be limited to shear pins in the worst case falls.

Fun to see people pushing the design limits. =3