Knowing that the target will be Mule Deer makes this a case of, which gun performs the best for your shooting style. All of your list can do well in the longer distance of Montana's open country...and also in the Mountain areas. If you were going for Elk, I would lean towards the heavier caliber and longer gun....but you aren't.
All other things being equal, and I have not fired some of your selection candidates, I would choose one of the BAR's. I had a 30-06 many years ago and loved that rifle. So Personal preference would be my deciding factor.