We got the 14-inch medium-firmness mattress to use on a "Swedish" (you know who I'm talkin' 'bout, right? ;-} ) queen bed frame. I hemmed and hawed for a while about purchasing this because we couldn't try it out first. We did NOT want to spend a king's ransom for a mattress, and we also didn't care whether it had a "name brand" or not. I wanted soft and hubby wanted firm, and this medium really is a good compromise for us. We are not small or slender people, by the way. This mattress is firm enough to be supportive, but not so firm as to be uncomfortable. We let it expand for about seven hours before we slept on it for the first time. The first night, we both noticed that it felt like we were going to roll off of the edges, but we previously had a full-sized bed and decided we needed to adjust to having a bit more room on the bed surface. Hubby also had concerns about it being "hot" to sleep on (he's very hot-natured), so I'd bought a quilted cotton mattress cover to put over it. We've had *zero* problems with it being "hot" to sleep on. This mattress sleeps like a dream and we could not be more pleased. UPDATE: I've been sleeping on this mattress for a little over 30 days now, and my lower back pain is GONE. Really GONE. I did some self-massage to get rid of tight spots left over from the old mattress, and the tight/problems spots are not coming back. I can't believe that a mattress could make that much difference, but apparently it does. BUY THIS MATTRESS. Seriously. I now plan to buy one of these for each bedroom.