doesn't this tiny rocket have very low range and bad efficiency compared to a traditional helicopter engine? the energy density of h2o2 is close to the one of a ion lithium battery (2.7MJ/Kg) vs the traditional gasoline+o2 (13.3 MJ/Kg) [1]. It seems like more a cool trick than something which can replace helicopter engines?

[1] https://en.wikipedia.org/wiki/Energy_density_Extended_Refere...