I got it to replace my older Shimano MW7 boots. Compared to Shimano's, those run just a smidge small (I had to get next size up, however wish there was an in-between). Sole seems stiffer, breathability is good, but feet still get a little sweaty. With thick wool sock is good down to freezing, with toe warmers maybe good to low to mid 20s. Unfortunately (fortunately?) have not had the chance to test them in the rain.
Shoes work well for me down into 30s. 20s require booties for me. 4 stars because of difficulty getting tongue and ankle wrap aligned properly when putting them on.