Let's start with the design. Ultraboost is the clear winner in this comparison. The elements are much smoother, more elegant, and the shapes are more futuristic and fresh. Although we believe some people might prefer the design of the Ultrabounce, Ultraboost clearly dominates in this aspect.
Next, let's compare the step-in comfort. Please note that this is not about overall comfort, but rather the initial feeling when you first put the shoes on. We have observed that Ultraboost feels a bit unnatural, with the heel lockdown being pulled forward and the toe box feeling a bit too tight. On the other hand, Ultrabounce feels a bit looser, which is better in terms of step-in comfort. It's a close call, but Ultrabounce has a slight advantage over Ultraboost in this comparison.
When it comes to lockdown, there is a clear winner here. Ultraboost's Primeknit mesh is extremely tight. On top of that, the extra reinforcement on the front, sides, and heel contribute to the exceptional level of lockdown. We would even call it the best on the market. Meanwhile, Ultrabounce, as mentioned earlier, feels a little bit loose. There is no good lockdown in the front, while the middle and back have a very good level but not as strong as in Ultraboost.
When we talk about ventilation, we have to admit that engineered mesh is always better compared to knit upper. Even though Ultrabounce has two-layered engineered mesh, it still ventilates a bit better than the knit on Ultraboost. You could argue that it is good for cold weather, but let's not forget that knit upper absorbs water much more, which means during cold periods, the knit upper will have an even bigger issue. So, all in all, Ultrabounce is the clear winner here.