I gotta say, my new 29er with knobby tires performs more like a road bike. I find myself sprinting up hills and carrying more speed on the flats. The frame geometry is different than my old Fisher 26, which may account for some of the difference. I also bought a larger frame, which gives me more room in the cockpit. As an old road racer, I am just 100% more at home on a 29er. It just feels right. I've really fallen for this new bike - it just does everything I want it to do. It also feels a lot more stable than my old MTB.

P.S. I bought a Specialized Rockhopper Comp 29er. It's still stock except for the saddle, clipless pedals, and Ergon grips and bar ends.