This is a great pair. The leg vents are great.
I wore a thin base layer and nothing else under it. In 23 degree weather I was comfortable. Later in the day it warmed up to about 38 maybe a little into the 40's. I zipped the leg vents open on the lifts going up the hill, zipped them back up before moving off again.
Absolutely perfect. Great fit. Zips to my jacket, locking out wind and snow from the few falls. Would buy 2 more.