You are looking at three of the four largest bike companies who all put out good products (Trek being the other). I agree about the fork travel possibly being a bonus point, and I personally prefer the feel of Shimano shifters/derailleurs over SRAM, but that’s all subjective. Another thing to consider is the LBS you’d be using (provided you are buying through one). If you can’t narrow down based on other factors you could always count what kind of deal you’d be getting and how you feel with the shop staff that you’d likely be dealing with. A good rapport goes a long way in my opinion. The only additional advice I can offer is to not rush the decision so that you’ll be happy when you pull the trigger.