I test rode one of these earlier this summer and while I was impressed with the power it had, I'm thinking others that are more power hungry than myself (I'm still a little overwhelmed by my 919) may feel a little empty. The turning on it was definitely a completely different animal. I've been told it's like turning a 4 wheeler, but as I've never ridden one I can't compare the two. I can say that it was a whole lot different than riding a bike thru a turn.
While I enjoyed the test ride, I definitely wouldn't trade in my bike for it, but that's just my opinion.
2003 Honda 919 - flapper mod, Clear Alternatives Smoke Tailight w/ integral turn signals, Stebel Nautilus air horn, DIY fender eliminator, LED license plate bolts, LED front turn signals, no resistor or new flasher so I blink like crazy.