Has any one used Jungle Scout or CamelCamelCamel

Hey, I was wondering how to search best products to sell on amazon. My friend one of the tech geek also an ecommerce nerd suggest me to go through some research work. I read jungle scout review ( https://www.withintheflow.com/reviews/jungle-scout/ ) in one day research and read also about camelcamelcamel. I wanna know which product should i go for ?