The mattress is definitely firm. I got it about a month ago when it was on sale and it’s  been decent. I put mine on the floor bc I’m too poor for some sort of bed structure atm. But it’s been cozy! It gives me the support I need  and I haven’t had any back problems. I’m probably going to get a pillow topper because this thing is firm and I don’t think I knew what FIRM meant. Set up was very easy. I did it myself and I am very small and not strong. For the price, it’s very nice. Would recommend.