I like these pants. I actually spent quite some time shopping for ski pants and ended up buying from Free Country, this being my very first order from them. I was attracted primarily by the form-fitting shape of these pants vs. the usual bulky ones. After reading the reviews on this pants running small, I ordered M, even though I normally wear size 4 to 5 (small). Shipping was fast. Somehow the package was open when delivered and being a snowy day, the pants were wet. This was not a big issue since these pants are water-proof. I put them on over jeans, fit nicely. After skiing for a while, the pants started getting a little loose. So I think that if you are size 6, M is for you, but if you are size 4, probably size S is better. However, this may not be a big issue as I usually wear pants underneath and you can also wear a belt to hold it in place. The quality is good. I like it being light-weight. Just one thing, the actual pants do not look as form-fitting as the picture, but they are definitely better-looking than the bulky ones.
Overall, these are good pants, and true to the size (wish I had ordered small). Also wish they price match because 3 days after getting my order, I found out they were offering 20% off for President's Day.