The Clarity is much faster than the Prius cars we've owned. That alone makes it seem fast because I never felt the Prius didn't serve our needs for acceleration. Perhaps the rare occasion passing a car on a 2 lane highway was the only time I had to make sure there was ample space. The Clarity does that much better. But around town the sensation of pushing the accelerator down when going 20-25 mpg and speeding up to 55 is quite fast but the biggest factor is the silence when accelerating. In most cases all I hear is the electric whine which I like. It just seems to be much faster than it is.