Initial and quick review of UltraBoost after 3 runs on the treadmill.
Let's start with the bad. It's hard to explain but there is definitely heel slippage on my pair and that is coming from a guy who sized down half when everyone else were staying tts or even sizing up half. The heel slippage only happens on faster runs, on walks of even slow jogs it is almost unnoticeable. The shoe is definitely snug on me for sure but if I were to try and guess what causes the heel slippage, it is probably that the primeknit is too pliable all over the place so your foot kind of pushes forward and stretches more than it should so it feel like the heel slips a bit? I think if the toe part of the primeknit were knitted tighter and less pliable, there wouldn't be this heel slip. Maybe the rear cushion could be tightened a bit? Again I am not 100% sure that is why but that would be my guess?
The next con is the rubber they used for the sole, while the web sole is great for heel to toe transition and flexibility, the rubber used is simply too soft. I've ran maybe 20 miles total in the treadmill, 3 times and the rubber were shredding already. See the pics below and you'll see what seems to be some rubber shavings and you'll see the little nubs on the sole are worn out. I can't imagine this shoes lasting too long at all sadly.
Now those are the major cons, the heel slippage is livable since I am a casual runner so it isn't a big deal. For those who run competitively and such, this can still be on regular run days. Now for the goods!
The obvious parts. Shoes is breathable, not much to be said. Wear white socks and you will literally see them through the upper. Speaking of the primeknit upper, the bootie single upper design is great, gives a real lockdown feel, almost too snug on the top so be aware of that if you have a high instep like I do. I think it'll eventually stretch and it'll be great. I know this kind of contradicts my reason for why there may be heel slippage but overall it is a snug fit that feels locked down but when doing faster runs it does moves a bit while still feeling locked where your shoe wouldn't necessarily come off. I am not sure if that makes sense. lol
The boost sole is very comfortable, really up there with cushioning in the game. It is simply great, not much needs to be said.
Speaking boost, it is hard to explain but I do believe it does work. As a disclaimer, this may be a placebo effect, I will test if further but this is my experience. I tend to run on a treadmill at a steady pace of 5-5.5 mph and when I do it in the UB, I feel like I was running on a 4mph speed, like I am going faster than I usually do on the same setting I run in every day. I guess the energy return and extra bounce does propel me a bit more so I feel like I am moving faster so as a result I had to bump the mph to 6.5-7 to feel like I am running my usual steady pace. I think this is something that you can only measure on a treadmill, I doubt I'd be able to tell on outdoor runs unless I time myself and measure my runs intensively, this was just easier to measure on the treadmill and was quite surprised. I'll say it again though, might be a placebo effect but I did find the experience very interesting to say the least.
Well I hope that's my brief review of the UB so far, it isn't a perfect shoe but still a very good one at that especially if you are like the others who doesn't experience heel slippage then the shoe will be much better for you.