Kreitler is known as the top-of-the-line for a good reason, no need to harp on the many good points to that end already made. The 2.25s, in my opinion, get somewhat of the short end of the stick - they are great for any serious athelete. I'm certainly not a world-level athelete, and these rollers provide the perfect level or resistance for a huge variety of rides - spinning at 60-80 in a low gear provides the same resistance as cruising on a long ride, granted your wheel is only spinning at 13-15mph, but you're not on a road, so what difference does it make? You still push a couple hundred watts for a couple hours. And for hard workouts and tempo rides? These rollers have a much higher theoretical top-end than the larger diameter versions, I can spin out in my highest gear on the bigger ones, can't on this one. This coupled with the wind-generator gives the broadest possible range of workouts of any of the Kreitler line, in my opinion.