I have been using this for one year and believe me it’s a very good kajal.as it tell this kajal is so deep n dark and smudge proof.but not for 10 hours for me as I live in a hot and humid climate.but it lasts how much I want it to i.e 4 to 5 hrs.it one advantage is it doesnt break easily if slips off ur hand which many a times happens to me. it has a good self life and longeivity.if the price could be litl less it would be awsm.