Non-personalized all the way, and for many, many reasons. Two off the top of my head: 1) You already bought the product, and now you see ads for it for the next

Non-personalized all the way, and for many, many reasons. Two off the top of my head: 1) You already bought the product, and now you see ads for it for the next x weeks; 2) You may not want other people (like maybe a spouse) to know you were browsing for something (like a gift, or perhaps even something untoward). On the second point, my spouse and I, each of us on our own devices, one of us can search for something, browse a website, and then the other one will start to see the ads for such in their Instagram feed (and for the record, it is usually me seeing the things my spouse is looking for). It is completely insidious and it needs to stop!