You can email them your preferrable models and sizes with "Step" before your trip, then you can pick it up when you arrive their shops in Tokyo or Osaka.
I did it for several times, it saved a lot of time.
Agreed. I brought 10 pairs of Asics Tarther and Skysensor (new Model TJR 013) for friends from Step few months ago. We saved approx. HK$300 per pair comparing with the discounted price from any of the professional shops in Hong Kong.
You can email them your preferrable models and sizes with "Step" before your trip, then you can pick it up when you arrive their shops in Tokyo or Osaka.