Quality is good. Some models appear to be susceptible to this issue:
I have experience with the New Guides and a pair whose name I don't remember that isn't on STP right now. The New Guides are nice for nostalgia, but just don't make the weight to support cut compared to mountaineering boots with glued on sole construction. The other pair are weight-wise somewhere in between the new guides and the rest of the models that STP has right now. They're very supportive in the ankle, but the midsole is so floppy I couldn't even use trail crampons with them because the sole curled up too much. Not exactly a win.
If I thought they were going to be supportive enough for the purpose, I would be tempted to try the "made in Italy backcountry hiking boots" by Alico. They look like they have the right amount of heel cup and are designed correctly to be good hikers.
Overall, I've completely abandoned trying to get boots without goretex. I still much prefer boots without goretex, but it's just too hard to get the right boots if you maintain that as a criteria. For example, I'll bet the Asolo Scafell (also on STP) offers better support per weight than the Alico and the PU midsole of the Asolo will be much more forgiving on the knees as you pound out the miles than the nylon shank of the Alico would be.