Blister prevention is the key. A proper fitting boot, with custom insoles will help, but not guarantee blister prevention. I take the crap out of my feet if I know I will have a real shit kicker hike, especially if there is lots of side hill work. Climbing straight up a mountain is particularly hard on the back of ones heels. I always tape the back of my heals, ankles and my arches, with blister bandages under the tape (athletic tape works the best) before a hard backpack hunt. I also take products in case I get blisters, but with the correct taping and blister bandages underneath, you can prevent hotspots and blisters. If the boot doesn't fit you correctly, you can get tissue and bone bruising and this is difficult to "fix" or prevent without the "right" boot. The key is to hike hard before your hunt, so you'll know where the boot is most likely to rub you. Then you can tape spots that are prone to blister, before you get a hot spot or blister.