The other night, while stretching, I was looking at my running shoes lying on the floor. The pink ones are the Saucony Rides - the ones that turn my heels into bastions of blisters. The blue ones are the Brooks Launch - the now discontinued shoe that gives me happy feet.
Since I spend a lot of time stretching it gave me time to really look at my shoes, and I noticed something in the way the back of the Saucony shoe is designed. Do you see how it bulges out in the back? And the Brooks shoe goes more or less straight down?
Can you see it better in this shot?
This may or may not be the cause, but it's different enough to make me suspect it. I know I will be paying attention to the shape of the back of my shoe from now on! LOL I'm not taking another risk of spending $100 for shoes that hurt me. Of course, I have learned the lesson that if the shoes are causing blisters, TAKE THEM BACK! Don't keep trying them out thinking that your feet will "toughen up"! ;)