I recently borrowed a Silvio. The intent was to ride it exclusively until I got used to it. The reality was, after only a few 10-15 mile rides, I found myself avoiding going for a ride because I detested the thing so much. I could cruise in a relatively straight line, as long as I was thinking about it. Startups were iffy. Moderate hills were do-able as long as I didn't stop. My overall exertion level was high and my average speeds were quite a bit lower. Overall, it was disappointing. I saw nothing about the Silvio that would make it faster than the bikes I already have; in fact the aerodynamics would argue for the Silvio being inherently slower. I think the guarantee banks on the idea that most people will be coming from even slower bikes, not that Cruzbikes are particularly fast.