I have done test rides on both the 2.1 Pilot, and a 2.3 . The 2.1 Pilot has a more relaxed geometry and is more comfortable. The 2.3 has a lighter more racy feel to it. The 2.3 felt like all your effort was making it to the ground where the 2.1 seemed a little sluggish, but more stable. So it depends on what kind of ridding you plan on doing, but either bike is nice. It just matters which one suits your purpose best.