I have been wear-testing this new line of gear from Mizuno this entire winter and have been very impressed with the results.
Since the middle of December, I have worn both the Breath Thermo upper and tights in many different conditions and have never had a bad thing to say about them. Simply put, this is the best cold weather gear I have ever owned.
Tights: While many other brands of tights consist of a thin layer of spandex and a pocket for your key, Mizuno tights are lined with the company's patented Breath Thermo layer. This not only keeps you warmer, but also gives the tights a soft feel that never chafes. One might think that with an extra layer added into the tights that they might bind or restrict movement when lengthening stride. I have never experienced such a problem, having worn these while doing tempo runs on flat roads and extended hill climbs up steep mountain trails. I can honestly say that I've run close to 600 miles in these tight since December, and have been comfortable and content for every single one of them. Great tights!
Fleece 1/2 Zip: This is a garment I have worn for about 60 days consecutively, whether I am running or relaxing, inside or outside. This piece of gear, more so than the tights, responds to the surrounding environment. Okay not literally, but its loose fit allows for more thermoregulation. It heats your body with the thermo technology, but is loose enough to allow air flow. On colder days (especially when its windy) you can combine this with a with a jacket layer and you'll stay toasty warm. Once again, this is a product I've used in varied conditions and the only place I've found it uncomfortable is in temperatures above 50 degrees (when its not needed).
Overall, I am ecstatic to have found such a great set of winter gear to run in. In my opinion, nothing that can compare to the Breath Thermo technology when it comes to battling the cold.
Now, I'm off to find a pair of Breath Thermo gloves!