Sheet masks are definitely among one of the most popular Asian skin care products. They're popular to the extent that Sephora now makes and sells their own brand of sheet masks (as I found out during my most recent visit). I've never used sheet masks that weren't from a Korean or Japanese brand, and I never buy sheet masks from Sephora (their own cost around $6 for one and the other Asian sheet masks they sell are usually more expensive). I am fortunate enough to have a local (ish, it's far away from my house) The Face Shop. It opened just a few months before I went abroad to study in Korea, so before I came back I thought I'd buy some of their sheet masks (which were on sale for 10+10!) and if I liked them, I could just continue to buy them conveniently from home. Recently they reformulated their sheet masks in the Real Nature line (갈아만든 line in Korean), so I'll be writing a comparison post today on the old vs. new formulas!