I've got very tough to fit feet as well. Very low volume, always heel lift and blisters, bone spurs and growths on the heels, etc….tried tango extremes, nepals, scarpa guides, mammuts, basically whatever I could find. Eventually got a pair of the Sportiva Barunteses with the moldable liners and its the best boot I've used. With a good aftermarket insole and a solid job molding, I can hike miles in them with no issues and lock my heels in place with no movement at all. Sure its a little heavy on long walks and sport mixed but anything from long moderate alpine ice to steep WI is great. Order them from backcountry, get them molded, and go try them out.