The comments in this make for interesting reading, and further down the owner/creator doesn't do themselves any marketing favours, or indeed any favours with the law of physics.
The clip with the shoe weighing down the pedal is interesting, that's movement for not a lot of force, but they don't seem to get that four gears on
any bike isn't really going to compete with the power/cadence range of even a 2x5 speed from decades ago. The lack of any substantive proof or even demonstration of the power benefits is a red flag.
It seems to attract ladies in bikini sports tops though so well worth £3k to me just for that.
edit: "There was so much power and torque going to the rear wheel, axles were literally twisting into pretzels." !!!!!