Hmmm, I have some, limited experience in these matters...............
I own a DiBlasi.................
Folding Motorbike! Bought in Saint Tropez in the 80s, I was arrested for smuggling it through London Gatwick Airport (pre EU, I had paid tax in France & used it for 7 months)
According to the Customs officials I was the 1st person in history to try to smuggle a motor vehicle through an airport!
The stainless steel version of the bicycle is ideal for use on your yacht BTW!
The trike version is ingenius & folds quickly to a fraction of it's normal size.
So DiBlasi gets my vote.
Big Fish :-
We took one to Spezi, and although everyone tried it, no-one liked to ride it, the components are too cheap & heavy.
Sue from Velovision rode it the 6 miles from our Bus to the show on the 1st day, she found it very hard going over the mixed road & forest tracks.
There were no takers for it on the Sunday and it was left in the Bus.
Pics to follow.......