I've had an Xcal 9 and I sold it and bought a Giant Fathom 1... much better bike in my opinion. I prefer 1 x for MTB and 2 x for road cycling and I don't think the 2 x is needed for mtn biking in my opinion unless maybe you plan to commute with it on downhills the 2 x would help but you can still go fast enough on a 1 x 11 if you have a high cadence.