Kosterina.com appears to be a legitimate website. The company, founded in 2016, specializes in premium Greek olive oil sourced from southern Greece. Reviews on various platforms, including Amazon and top consumer review sites, indicate a high level of customer satisfaction with their products. The olive oil is praised for its fruity-yet-peppery flavor and high polyphenol content. The website offers subscription options and free shipping within the continental US. However, some customers have noted the importance of checking expiration dates on the products. Overall, Kosterina.com seems to be a reputable source for high-quality olive oil.