The Boston's fit is more like that of the Adios—a little lower around the ankle. Also, the upper is from the same lightweight mesh. The big difference between the models is that the Boston has the "thickest" midsole in the lightweight trainers range from Adidas. Its weight is 9.7 oz.

The heel is about the same as in the Ace but the forefoot is beefed up with some extra cushioning as well as some durability due to the use of blown rubber on the outsole. This, as opposed to the lighter Adidas Quickstrike, used on the Adios and the Ace.

It would have been nice to see this model with a medial post; Adidas would have created a nice balance between its neutral and more supportive models. Too bad they didn't. This is in my opinion a missed opportunity, since they now have three neutral models—pretty close to each other—and only one model (the Mana) with some added medial support.

The Boston is also available in a womens-specific model in the same color as the men’s version.

As an aside, just over a year ago triathlete Dave Jewell, then working for Adidas, started a discussion on the Slowtwitch Reader Forum explaining the shoes in the Adizero category. It's slightly dated, but, still has legs (even though Dave now works for Zoot's footwear division), especially since forum threads often have a way of keeping themselves current.