After almost 8 months it's still perfect for us, No sagging.  It was highly rated by consumer reports and they mentioned that it's on the firmer side which we wanted. Since we have had such bad luck choosing mattresses from local stores that we have gone and tested, we decided to take a chance on this one online. So glad we did! Nice and firm with no indentations where we sleep so far. I'll update if anything changes. We also liked the Wayfair guarantee and their customer service is good as well. Don't get it if you like a squishy memory foam type mattress though. We were looking for more of a hotel type mattress and this one reminds me of that type.