Started using the ASICS a few weeks before the marathon, I think with the last 20 mile training run, and I was rotating pairs for the last few weeks of training. So I probably got to Tokyo with about 60-70 miles in the new pair, which I was expecting to get some runs in with on vacation (lol). I've always had trouble with my normal pairs of shoes on park days, just a lot of time on your feet that leaves me feeling sore, so that's why I started using the running shoes as park shoes at the DL half weekend, and it felt fine at the time. In this case I used the ASICS for TDL, Universal Osaka, and a couple other full days of walking around, and when I got back to training it just felt like the ASICS weren't as cushiony as they had been. So I started thinking about it and I'm looking at 12-16 hours a day, four days of using these running shoes for not-running, and it feels like it just adds up. A lot of walking around, and a lot of downward pressure on the soles when you're just standing around.