NASA and the French aerospace agency have conducted research into magnetic suspension and balancing systems (MSBS) to suspend models during wind tunnel tests, like this system in South Korea.

1. Where did the NASA and ONERA research lead?
2. If MSBS reduces interference from the springs and arms that usually hold models, why don't all wind tunnels use this technology? What are the disadvantages?

Also, can somebody create a wind-tunnel or wind-tunnel-testing tag?