Salomon Conquest GTX here.
I have used mountain boots from the "big three" Euro manufacturers (Scarpa, Lowa, La Sportiva), and despite high-end footbeds, attempts to properly fit, and countless models, they all eventually give me heel blisters. It's important to note that the blisters really only happen on long uphills, but they happen nevertheless. I do have an awkward foot (wide forefoot, heavy overpronation and narrow ankle), but I find that any "mountain-specific" boot is simply too stiff for the movement that occurs in my ankle and mid-foot, thus creating hotspots and blisters.
Enter the Salomons: Most comfortable boots I've ever owned. Now I have no illusions that these boots offer the same support, protection, or longevity as my mountain boots that cost triple the price, but they sure feel fantastic.
I've carried upwards of 100lbs on my back and have no issues with these boots. They are supremely comfortable, zero hot spots, and after a long day I'm in no hurry to take them off.
All feet are different of course, but if you have heel issues (especially narrow heel and wide forefoot) these are a strong contender.