So, last I heard, there was speculation the Martin Jetpack couldn't fly outside of ground effect. The video doesn't disprove that, but it's still lots of fun to watch.
The engine is pretty cool. Though I have a feeling that they could still do better with a turbine. I mean if Wendell Moore could make a smaller jetpack than this in the 1960's, imagine what we can do today with inconel and hastelloy...
(Also, let's not forget that this was also done in the early 2000's by the SoloTrek.)