My Moots MootoX YBB 29er has now provided me with about 8,000 feet of climbing over some 80 miles or so. I am extremely pleased with the ride quality in every respect.
In spite of the additional weight (heavier shock and rear YBB mechanism), the MootoX YBB 29er might be my favorite ride yet— very, very efficient to climb, and a rocket downhill with high precision navigation due to the beefier shock. And the gain in comfort over the MootoX RSL is quite significant on the lumpy trails that I ride. I plan to alternate between the RSL and the YBB to ferret out all the nuances over time, but that will take a few weeks of riding.