Hacivat is one of my favourites in my collections. It was my first Niche fragrance and the reason I stopped buying cheapies. I was excited when I first found out about Hacivat X. I only had the 50 mL of Hacivat and it was time to decide to buy a bigger bottle or just go with X. I decided to go with Hacivat X. They smell very similar but X is much weaker and you can really smell the lime note. I would say wear Hacivat in the Fall and Winter and Hacivat X in the Spring and Summer. Overall I am happy with my purchase.