the pothole test is bolloks, that is not a hole but a dip, very different. All being said it does seem quite stable although I'm sure the rider is well trained. I would be feaful of it's safety to be honest, all well and good until your in a sticky spot in town. I got a mondeo because I was not happy with the safety and power of my atoz. In the same logic I'd take a traditional bike over the Yike as it's more versatile in trafic and I can ram it to a low gear and get moving fast if I need to, the Yike cleaerly would not have that power. Knowing my ride to work I'd not take a yike on it, for one thing I missed the lights ? no lights = no good.
To be honest the price is just right, it completely fills the office wanker factor. If you think of it it's aimed at that sector of people who probably have the cash and would not be seen dead on a bycycle let alone live. However if they get to spend that much money on this gadget it will justify them using it, they will buy it in the spring and only realize 6 months later that without lights it's doomed.
It's like when they brought the bike2work scheme to my work place. People started touting about the thousands they'd be spending on a bike, I just laughed at them - my bike is a rusty old thing that none the less is mechanically sound that I was given and I'm quite happy to do a 40 mile treck on it should I feel like it, but no some people in my workplace have to spend about £1500 to justify using it.