Montrails tend to be reasonably true to size, but their hallmark is a narrower heel and instep with a noticeable arch and typically with a noticeably wider toe box.
I can't wear standard Montrail because my instep is quite wide and I have bruised my instep/arch severely on them. However, I have been very happy with the wide version of the Hardrock. As mentioned earlier, if you are a 9.5 with he Salomon XA series, go with the 9.5 in Montrails.
The XA series tends to best fit those with medium or narrower heels also, so you will likely get a solid fit in Montrails. The Hardrock is a good functioning shoe compared to the ventilated XA Comp (though just a bit heavier), while the Hurricane Ridge is a good option if you want Goretex.