I haven't seen enough details to have a good opinion, but I'm skeptical (but would happily eat my hat if it works). We abandoned mirror fusion in the 80's because confinement is really hard if you have open field lines [1]. I do think high beta confinement concepts ([2], [3]) are very cool and could drive power plants small enough for power companies to be interested.
[1] http://en.wikipedia.org/wiki/Mirror_Fusion_Test_Facility [2] http://en.wikipedia.org/wiki/Spheromak [3] http://en.wikipedia.org/wiki/Spherical_tokamak