Have a pair Strands and I love them. Wear them on average 4 days per week, walking to the subway and back for work (.5 miles each way), and then around in a carpeted office. Wear occasionally on weekends. I've had then for a little less than 18 months and I've already worn through the rubber heel section, and a small hole has developed in the forefoot, exposing the cork base (i.e. the leather sole has worn through.) Is this normal, or were the shoes defective? I didn't think I'd need a recrafting in less than 2 years. Thoughts?