The John Frieda Frizz Ease Extra Strength Serum is widely regarded as highly effective for frizz reduction and control. Users frequently report that it leaves hair shiny, smooth, and soft without feeling greasy or heavy. Many find it performs well in humid conditions and helps manage flyaways. It is often recommended by reviewers, including those with thick, curly, wavy, or coarse hair. A common comment is that a small amount of product provides lasting results, contributing to its perceived value. The serum's scent is generally well-received. Some users note that improper application can result in an oily appearance. The product is frequently repurchased by long-term users, who often apply it to damp or wet hair. Additionally, some users find it beneficial for addressing hair dryness.