I’ve just sold my Trek/GF rumblefish 29er and have a Niner Air9 for Sale, and bought a 26 Lapierre Zesty 514. I did look at an X29er and to be honest it just looked really flimsy in comparison, it looks like it should be ridden by someone at least 8ft tall, all out of proportion… I’ve experienced the benefits of 29er wheels and whist they roll really well and the rumblefish was a monster downhill bike I’ve not thought twice about buying another 26er Zesty 514. It feels mega light in comparison even with a 21.5 frame (both rumblefish and the Niner are 19″ and I’m 6ft) but each to their own….