About 20 years ago I bought my first Birkenstock boston. He has held until about 2 months - but he was also really by! For cheap goods I would therefore spent far more money, because that would have never thought so long. Now I have new Birkenstock, the wonderfully feels the foot. For me the best slipper, I can imagine. How long the hold then? I can probably write only in 15-20 years.