ZCoil Z Coil Shoes

I did all my homework on the Zcoil shoes before buying, but there was one thing I did not think to ask and found out only by experience: How much do the heels cost to replace? How long do they last?I have had my shoes 9 months. One of the coils has worn a hole thru the heel. I weigh about 155lbs and walk approx. 10 miles a week. I have never worn out heels on even the cheap shoes. I thought it would be under warranty because they said the coil is under warranty. But it is NOT under warranty. And the cost to replace the heels is $35! When I discovered that these expensive shoes seem to have a flaw in their design, and would cost me $35 every 9 months or so, I was hurt. I called their HQ in N.M., and the gentleman I spoke with said that was not unusual, that some runners wear them thru in 2 weeks!!!! Hello? Is that not a design problem, or what? So I am stuck with the most expensive pair of shoes I have ever purchased, and will soon not be able to use them.