Heat molding a Salomon, Head, Fischer, etc... allows for a certain amount of additional space to be made IF the fitter knows how to prep your foot for the process. If you have a very narrow foot, there is no way to make a heat mold able shell smaller or lessen the volume. A competent fitter could easily name 3-4 boots with less volume than a women's Salomon X-max. You might fit into an X-max, or you might not. It's just not a very good idea to base one's boot choice on another's especially when using vague descriptors like 'narrow'. High instep? Low instep? Well defined achilles? Wide or narrow talus? What about calf mass and location? Any cuff alignment issues? Different boots have very different capacities for adjustment. Shimable? Planeable? These are all favors in the realm of 'narrow' that can be critical to good fit. A good boot guy/gal knows this.
If you were following this post, you would have realized that I had asked her specifically about the insoles and the insoles only. Not an enitre boot.